| pigs(1) | pigpio archive | pigs(1) |
pigs - command line socket access to the pigpio daemon.
/dev/pigpio - command line pipe access to the pigpio daemon.
sudo pigpiod
then
pigs {command}+
or
echo {command}+ >/dev/pigpio
The socket and pipe interfaces allow control of the Pi's GPIO by passing messages to the running pigpio library.
The normal way to start the pigpio library would be as a daemon during boot.
sudo pigpiod
o hardware timed PWM on any of GPIO 0-31
o hardware timed servo pulses on any of GPIO 0-31
o reading/writing all of the GPIO in a bank as one operation
o individually setting GPIO modes, reading and writing
o notifications when any of GPIO 0-31 change state
o the construction of output waveforms with microsecond timing
o I2C, SPI, and serial link wrappers
o creating and running scripts on the pigpio daemon
ALL GPIO are identified by their Broadcom number.
pigs is a program and internally uses the socket interface to pigpio whereas /dev/pigpio uses the pipe interface.
pigs and the pipe interface share the same commands and are invoked in a similar fashion from the command line.
The pigpio library must be running, either by running a program linked with the library or starting the pigpio daemon (sudo pigpiod).
pigs {command}+
echo "{command}+" >/dev/pigpio
pigs will show the result of the command on screen.
The pigs process returns an exit status (which can be displayed with the command echo $?).
PIGS_OK 0
PIGS_CONNECT_ERR 255
PIGS_OPTION_ERR 254
PIGS_SCRIPT_ERR 253
The results of /dev/pigpio commands need to be read from /dev/pigout, e.g. cat /dev/pigout (try cat /dev/pigout& so that all subsequent results are shown on screen).
In both cases if an error was detected a message will have been written to /dev/pigerr (try cat /dev/pigerr&). This is likely to be more informative than the message returned by pigs or the error code returned by the pipe interface.
Several commands may be entered on a line. If present PROC and PARSE must be the last command on a line.
E.g.
pigs w 22 1 mils 1000 w 22 0
is equivalent to
pigs w 22 1
pigs mils 1000
pigs w 22 0
and
echo "m 4 w w 4 0 mils 250 m 4 r r 4" >/dev/pigpio
is equivalent to
echo "m 4 w" >/dev/pigpio
echo "w 4 0" >/dev/pigpio
echo "mils 250" >/dev/pigpio
echo "m 4 r" >/dev/pigpio
echo "r 4" >/dev/pigpio
The examples from now on will show the pigs interface but the same commands will also work on the pipe interface.
pigs does not show the status of successful commands unless the command itself returns data. The status (0) will be returned to pigs but will be discarded.
The status/data of each command sent to the pipe interface should be read from /dev/pigout.
When a command takes a number as a parameter it may be entered as hex (precede by 0x), octal (precede by 0), or decimal.
E.g. 23 is 23 decimal, 0x100 is 256 decimal, 070 is 56 decimal.
Some commands can return a variable number of data bytes. By default this data is displayed as decimal. The pigs -a option can be used to force the display as ASCII and the pigs -x option can be used to force the display as hex.
E.g. assuming the transmitted serial data is the letters ABCDEONM
$ pigs slr 4 100
8 65 66 67 68 69 79 78 77
$ pigs -a slr 4 100
8 ABCDEONM
$ pigs -x slr 4 100
8 41 42 43 44 45 4f 4e 4d
M/MODES g m Set GPIO mode
MG/MODEG g Get GPIO mode
PUD g p Set GPIO pull up/down
R/READ g Read GPIO level
W/WRITE g L Write GPIO level
P/PWM u v Set GPIO PWM value
PFS u v Set GPIO PWM frequency
PRS u v Set GPIO PWM range
GDC u Get GPIO PWM dutycycle
PFG u Get GPIO PWM frequency
PRG u Get GPIO PWM range
PRRG u Get GPIO PWM real range
S/SERVO u v Set GPIO servo pulsewidth
GPW u Get GPIO servo pulsewidth
TRIG u pl L Send a trigger pulse
WDOG u v Set GPIO watchdog
BR1 Read bank 1 GPIO
BR2 Read bank 2 GPIO
BC1 bits Clear specified GPIO in bank 1
BC2 bits Clear specified GPIO in bank 2
BS1 bits Set specified GPIO in bank 1
BS2 bits Set specified GPIO in bank 2
NO Request a notification
NC h Close notification
NB h bits Start notification
NP h Pause notification
HC g cf Set hardware clock frequency
HP g pf pdc Set hardware PWM frequency and dutycycle
FG u stdy Set a glitch filter on a GPIO
FN u stdy actv Set a noise filter on a GPIO
PADS pad padma Set pad drive strength
PADG pad Get pad drive strength
SHELL name str Execute a shell command
CF1 uvs Custom function 1
CF2 uvs Custom function 2
EVM h bits Set events to monitor
EVT event Trigger event
PROC t Store script
PROCR sid pars Run script
PROCU sid pars Set script parameters
PROCP sid Get script status and parameters
PROCS sid Stop script
PROCD sid Delete script
PARSE t Validate script
I2CO ib id if Open I2C bus and device with flags
I2CC h Close I2C handle
I2CWQ h bit smb Write Quick: write bit
I2CRS h smb Read Byte: read byte
I2CWS h bv smb Write Byte: write byte
I2CRB h r smb Read Byte Data: read byte from register
I2CWB h r bv smb Write Byte Data: write byte to register
I2CRW h r smb Read Word Data: read word from register
I2CWW h r wv smb Write Word Data: write word to register
I2CRK h r smb Read Block Data: read data from register
I2CWK h r bvs smb Write Block Data: write data to register
I2CWI h r bvs smb Write I2C Block Data
I2CRI h r num smb Read I2C Block Data: read bytes from register
I2CRD h num i2c Read device
I2CWD h bvs i2c Write device
I2CPC h r wv smb Process Call: exchange register with word
I2CPK h r bvs smb Block Process Call: exchange data bytes with register
I2CZ h bvs Performs multiple I2C transactions
BI2CO sda scl b Open bit bang I2C
BI2CC sda Close bit bang I2C
BI2CZ sda bvs I2C bit bang multiple transactions
BSCX bctl bvs BSC I2C/SPI transfer
SERO dev b sef Open serial device dev at baud b with flags
SERC h Close serial handle
SERRB Read byte from serial handle
SERWB h bv Write byte to serial handle
SERR h num Read bytes from serial handle
SERW h bvs Write bytes to serial handle
SERDA h Check for serial data ready to read
SLRO u b db Open GPIO for bit bang serial data
SLRC u Close GPIO for bit bang serial data
SLRI u v Sets bit bang serial data logic levels
SLR u num Read bit bang serial data from GPIO
SPIO c b spf SPI open channel at baud b with flags
SPIC h SPI close handle
SPIR h num SPI read bytes from handle
SPIW h bvs SPI write bytes to handle
SPIX h bvs SPI transfer bytes to handle
BSPIO cs miso mosi sclk b spf Open bit bang SPI
BSPIC cs Close bit bang SPI
BSPIX cs bvs SPI bit bang transfer
FO file mode Open a file in mode
FC h Close file handle
FR h num Read bytes from file handle
FW h bvs Write bytes to file handle
FS h num from Seek to file handle position
FL pat num List files which match pattern
WVCLR Clear all waveforms
WVNEW Initialise a new waveform
WVAG trips Add generic pulses to waveform
WVAS u b db sb o bvs Add serial data to waveform
WVCRE Create a waveform
WVCAP percent Create a waveform of fixed size
WVDEL wid Delete selected waveform
WVTX wid Transmits waveform once
WVTXM wid wmde Transmits waveform using mode
WVTXR wid Transmits waveform repeatedly
WVCHA bvs Transmits a chain of waveforms
WVTAT Returns the current transmitting waveform
WVBSY Check if waveform is being transmitted
WVHLT Stop waveform
WVSC ws Get waveform DMA CB stats
WVSM ws Get waveform time stats
WVSP ws Get waveform pulse stats
H/HELP Display command help
HWVER Get hardware version
MICS v Microseconds delay
MILS v Milliseconds delay
PIGPV Get pigpio library version
T/TICK Get current tick
CGI Configuration get internals
CSI v Configuration set internals
Upon success nothing is returned. On error a negative status code will be returned.
Example
$ pigs bc1 0x400010 # clear GPIO 4 (1<<4) and 22 (1<<22)
$ pigs bc1 32 # clear GPIO 5 (1<<5)
-42
ERROR: no permission to update one or more GPIO
Upon success nothing is returned. On error a negative status code will be returned.
Example
$ pigs bc2 0x8000 # clear GPIO 47 (activity LED on A+/B+/Pi2/Pi3)
$ pigs bc2 1 # clear GPIO 32 (first in bank 2)
-42
ERROR: no permission to update one or more GPIO
Example
$ pigs bi2cc 5
Bit banging I2C allows for certain operations which are not possible with the standard I2C driver.
o baud rates as low as 50
o repeated starts
o clock stretching
o I2C on any pair of spare GPIO
The baud rate may be between 50 and 500000 bits per second.
The GPIO used for SDA and SCL must have pull-ups to 3V3 connected. As a guide the hardware pull-ups on pins 3 and 5 are 1k8 in value.
The following command codes are supported:
Name Cmd & Data Meaning
End 0 No more commands
Escape 1 Next P is two bytes
Start 2 Start condition
Stop 3 Stop condition
Address 4 P Set I2C address to P
Flags 5 lsb msb Set I2C flags to lsb + (msb << 8)
Read 6 P Read P bytes of data
Write 7 P ... Write P bytes of data
The address, read, and write commands take a parameter P. Normally P is one byte (0-255). If the command is preceded by the Escape command then P is two bytes (0-65535, least significant byte first).
The address and flags default to 0. The address and flags maintain their previous value until updated.
No flags are currently defined.
Example
Set address 0x53
start, write 0x32, (re)start, read 6 bytes, stop
Set address 0x1E
start, write 0x03, (re)start, read 6 bytes, stop
Set address 0x68
start, write 0x1B, (re)start, read 8 bytes, stop
End
0x04 0x53
0x02 0x07 0x01 0x32 0x02 0x06 0x06 0x03
0x04 0x1E
0x02 0x07 0x01 0x03 0x02 0x06 0x06 0x03
0x04 0x68
0x02 0x07 0x01 0x1B 0x02 0x06 0x08 0x03
0x00
Example
$ pigs br1
1001C1CF
Example
$ pigs br2
003F0000
Upon success nothing is returned. On error a negative status code will be returned.
Example
$ pigs bs1 16 # set GPIO 4 (1<<4)
$ pigs bs1 1 # set GPIO 1 (1<<0)
-42
ERROR: no permission to update one or more GPIO
Upon success nothing is returned. On error a negative status code will be returned.
Example
$ pigs bs2 0x40 # set GPIO 38 (enable high current mode A+/B+/Pi2/Pi3)
$ pigs bs2 1 # set GPIO 32 (first in bank 2)
-42
ERROR: no permission to update one or more GPIO
This command performs a BSC I2C/SPI slave transfer as defined by bctl with data bvs.
This function provides a low-level interface to the SPI/I2C Slave peripheral on the BCM chip.
This peripheral allows the Pi to act as a hardware slave device on an I2C or SPI bus.
This is not a bit bang version and as such is OS timing independent. The bus timing is handled directly by the chip.
The output process is simple. You simply append data to the FIFO buffer on the chip. This works like a queue, you add data to the queue and the master removes it.
I can't get SPI to work properly. I tried with a control word of 0x303 and swapped MISO and MOSI.
The command sets the BSC mode and writes any data bvs to the BSC transmit FIFO. It returns the data count (at least 1 for the status word), the status word, followed by any data bytes read from the BSC receive FIFO.
Note that the control word sets the BSC mode. The BSC will stay in that mode until a different control word is sent.
For I2C use a control word of (I2C address << 16) + 0x305.
E.g. to talk as I2C slave with address 0x13 use 0x130305.
GPIO used for models other than those based on the BCM2711.
SDA SCL MOSI SCLK MISO CE I2C 18 19 - - - - SPI - - 18 19 20 21
GPIO used for models based on the BCM2711 (e.g. the Pi4B).
SDA SCL MOSI SCLK MISO CE I2C 10 11 - - - - SPI - - 10 11 9 8
When a zero control word is received the used GPIO will be reset to INPUT mode.
The control word consists of the following bits.
22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
a a a a a a a - - IT HC TF IR RE TE BK EC ES PL PH I2 SP EN
Bits 0-13 are copied unchanged to the BSC CR register. See pages 163-165 of the Broadcom peripherals document for full details.
aaaaaaa defines the I2C slave address (only relevant in I2C mode)
IT invert transmit status flags
HC enable host control
TF enable test FIFO
IR invert receive status flags
RE enable receive
TE enable transmit
BK abort operation and clear FIFOs
EC send control register as first I2C byte
ES send status register as first I2C byte
PL set SPI polarity high
PH set SPI phase high
I2 enable I2C mode
SP enable SPI mode
EN enable BSC peripheral
The returned status has the following format
20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
S S S S S R R R R R T T T T T RB TE RF TF RE TB
Bits 0-15 are copied unchanged from the BSC FR register. See pages 165-166 of the Broadcom peripherals document for full details.
SSSSS number of bytes successfully copied to transmit FIFO
RRRRR number of bytes in receieve FIFO
TTTTT number of bytes in transmit FIFO
RB receive busy
TE transmit FIFO empty
RF receive FIFO full
TF transmit FIFO full
RE receive FIFO empty
TB transmit busy
This example assumes that GPIO 2/3 are connected to GPIO 18/19 (GPIO 10/11 on the BCM2711).
Example
$ pigs bscx 0x130305 # start BSC as I2C slave 0x13
1 18
$ i2cdetect -y 1
0 1 2 3 4 5 6 7 8 9 a b c d e f
00: -- -- -- -- -- -- -- -- -- -- -- -- --
10: -- -- -- 13 -- -- -- -- -- -- -- -- -- -- -- --
20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
70: -- -- -- -- -- -- -- --
$ pigs i2co 1 0x13 0 # get handle for device 0x13 on bus 1
0
$ pigs i2cwd 0 90 87 51 9 23 # write 5 bytes
$ pigs bscx 0x130305 # check for data
6 18 90 87 51 9 23
$ pigs bscx 0x130305 11 13 15 17 # check for data and send 4 bytes
1 262338
$ pigs i2crd 0 4 # read 4 bytes
4 11 13 15 17
$ pigs i2cwd 0 90 87 51 9 23 # write 5 bytes
$ pigs bscx 0x130305 11 13 15 17 # check for data and send 4 bytes
6 262338 90 87 51 9 23
$ pigs i2crd 0 4
4 11 13 15 17
$ pigs bscx 0x130305 22 33 44 55 66
1 327938
$ pigs i2crd 0 5
5 22 33 44 55 66
This command stops bit banging SPI on a set of GPIO opened with BSPIO.
The set of GPIO is specifed by cs.
Upon success nothing is returned. On error a negative status code will be returned.
Example
$ pigs bspic 10
$ pigs bspic 10
-142
ERROR: no bit bang SPI in progress on GPIO
This command starts bit banging SPI on a group of GPIO with slave select cs, MISO miso, MOSI mosi, and clock sclk.
Data will be transferred at baud b bits per second (which may be set in the range 50-250000).
The flags spf may be used to modify the default behaviour of mode 0, active low chip select.
The flags consists of the least significant 22 bits.
21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
0 0 0 0 0 0 R T 0 0 0 0 0 0 0 0 0 0 0 p m m
mm defines the SPI mode.
Mode POL PHA
0 0 0
1 0 1
2 1 0
3 1 1
p is 0 if CS is active low (default) and 1 for active high.
T is 1 if the least significant bit is transmitted on MOSI first, the default (0) shifts the most significant bit out first.
R is 1 if the least significant bit is received on MISO first, the default (0) receives the most significant bit first.
The other bits in flags should be set to zero.
Upon success 0 is returned. On error a negative status code will be returned.
If more than one device is connected to the SPI bus (defined by SCLK, MOSI, and MISO) each must have its own CS.
Example
$ pigs bspio 9 11 12 13 50000 0
$ pigs bspio 10 11 12 13 50000 0
$ pigs bspio 29 19 20 21 50000 0 # GPIO 29 not avaialble on this Pi
-41
ERROR: no permission to update GPIO
This command writes bytes bvs to the bit bang SPI device associated with slave select cs. It returns the same number of bytes read from the device.
Upon success the count of returned bytes followed by the bytes themselves is returned. On error a negative status code will be returned.
Example
$ pigs bspio 5 13 19 12 10000 0 # MCP4251 DAC
$ pigs bspio 6 13 19 12 20000 3 # MCP3008 ADC
$ pigs bspix 5 0 16 # set DAC to 16
2 255 255
$ pigs bspix 5 12 0 # read back DAC
2 254 16
$ pigs bspix 6 1 128 0 # read ADC input 0
3 0 3 184 # 952
$ pigs bspix 5 0 240 # set DAC to 240
2 255 255
$ pigs bspix 5 12 0 # read back DAC
2 254 240
$ pigs bspix 6 1 128 0 # read ADC input 0
3 0 0 63 # 63
$ pigs bspix 5 0 128 # set DAC to 128
2 255 255
$ pigs bspix 5 12 0 # read back DAC
2 254 128
$ pigs bspix 6 1 128 0 # read ADC input 0
3 0 1 255 # 511
$ pigs bspic 5 # close SPI CS 5
$ pigs bspic 6 # close SPI CS 6
$ pigs bspic 5 # try to close SPI CS 5 again
-142
ERROR: no bit bang SPI in progress on GPIO
This command calls a user customised function. The meaning of any paramaters and the returned value is defined by the customiser.
This command calls a user customised function. The meaning of any paramaters and the returned value is defined by the customiser.
Upon success nothing is returned. On error a negative status code will be returned.
The notification gets reports for each event specified by bits.
Example
$ pigs evm 0 -1 # Shorthand for events 0-31.
$ pigs evm 0 0xf0 # Get notifications for events 4-7.
$ pigs evm 1 0xf
-25
ERROR: unknown handle
One event, number 31, is predefined. This event is auto generated on BSC slave activity.
Example
$ pigs evt 12
$ pigs evt 5
$ pigs evt 32
-143
ERROR: bad event id
Upon success nothing is returned. On error a negative status code will be returned.
Example
$ pigs fc 0 # First close okay.
$ pigs fc 0 # Second fails.
-25
ERROR: unknown handle
Level changes on the GPIO u are not reported unless the level has been stable for at least stdy microseconds. The level is then reported. Level changes of less than stdy microseconds are ignored.
The filter only affects callbacks (including pipe notifications).
The R/READ, BR1, and BR2 commands are not affected.
Note, each (stable) edge will be timestamped stdy microseconds after it was first detected.
Example
$ pigs fg 4 250
$ pigs fg 4 1000000
-125
ERROR: bad filter parameter
Upon success the count of returned bytes followed by the matching files is returned. On error a negative status code will be returned.
A newline (0x0a) character separates each file name.
Only files which have a matching entry in /opt/pigpio/access may be listed.
Suppose /opt/pigpio/access contains
/sys/bus/w1/devices/28*/w1_slave r
Example
$ pigs -a fl "/sys/bus/w1/devices/28*/w1_slave" 5000
90 /sys/bus/w1/devices/28-000005d34cd2/w1_slave
/sys/bus/w1/devices/28-001414abbeff/w1_slave
$ pigs -a fl "/sys/bus/*" 5000
ERROR: no permission to access file
-137
Level changes on the GPIO u are ignored until a level which has been stable for stdy microseconds is detected. Level changes on the GPIO are then reported for actv microseconds after which the process repeats.
The filter only affects callbacks (including pipe notifications).
The R/READ, BR1, and BR2 commands are not affected.
Note, level changes before and after the active period may be reported. Your software must be designed to cope with such reports.
Example
$ pigs fn 7 250 1000
$ pigs fn 7 2500000 1000
-125
ERROR: bad filter parameter
Upon success a handle (>=0) is returned. On error a negative status code will be returned.
File
A file may only be opened if permission is granted by an entry in /opt/pigpio/access. This is intended to allow remote access to files in a more or less controlled manner.
Each entry in /opt/pigpio/access takes the form of a file path which may contain wildcards followed by a single letter permission. The permission may be R for read, W for write, U for read/write, and N for no access.
Where more than one entry matches a file the most specific rule applies. If no entry matches a file then access is denied.
Suppose /opt/pigpio/access contains the following entries
/home/* n
/home/pi/shared/dir_1/* w
/home/pi/shared/dir_2/* r
/home/pi/shared/dir_3/* u
/home/pi/shared/dir_1/file.txt n
Files may be written in directory dir_1 with the exception of file.txt.
Files may be read in directory dir_2.
Files may be read and written in directory dir_3.
If a directory allows read, write, or read/write access then files may be created in that directory.
In an attempt to prevent risky permissions the following paths are ignored in /opt/pigpio/access.
a path containing ..
a path containing only wildcards (*?)
a path containing less than two non-wildcard parts
Mode
The mode may have the following values.
Value Meaning READ 1 open file for reading WRITE 2 open file for writing RW 3 open file for reading and writing
The following values may be or'd into the mode.
Value Meaning APPEND 4 All writes append data to the end of the file CREATE 8 The file is created if it doesn't exist TRUNC 16 The file is truncated
Newly created files are owned by root with permissions owner read and write.
Example
$ ls /ram/*.c
/ram/command.c /ram/pigpiod.c /ram/pigs.c
/ram/x_pigpiod_if.c /ram/pig2vcd.c /ram/pigpiod_if2.c
/ram/x_pigpio.c /ram/x_repeat.c /ram/pigpio.c
/ram/pigpiod_if.c /ram/x_pigpiod_if2.c
# assumes /opt/pigpio/access contains the following line
# /ram/*.c r
$ pigs fo /ram/pigpio.c 1
0
$ pigs fo /ram/new.c 1
-128
ERROR: file open failed
$ pigs fo /ram/new.c 9
1
$ ls /ram/*.c -l
-rw-r--r-- 1 joan joan 42923 Jul 10 11:22 /ram/command.c
-rw------- 1 root root 0 Jul 10 16:54 /ram/new.c
-rw-r--r-- 1 joan joan 2971 Jul 10 11:22 /ram/pig2vcd.c
-rw------- 1 joan joan 296235 Jul 10 11:22 /ram/pigpio.c
-rw-r--r-- 1 joan joan 9266 Jul 10 11:22 /ram/pigpiod.c
-rw-r--r-- 1 joan joan 37331 Jul 10 11:22 /ram/pigpiod_if2.c
-rw-r--r-- 1 joan joan 33088 Jul 10 11:22 /ram/pigpiod_if.c
-rw-r--r-- 1 joan joan 7990 Jul 10 11:22 /ram/pigs.c
-rw-r--r-- 1 joan joan 19970 Jul 10 11:22 /ram/x_pigpio.c
-rw-r--r-- 1 joan joan 20804 Jul 10 11:22 /ram/x_pigpiod_if2.c
-rw-r--r-- 1 joan joan 19844 Jul 10 11:22 /ram/x_pigpiod_if.c
-rw-r--r-- 1 joan joan 19907 Jul 10 11:22 /ram/x_repeat.c
Upon success the count of returned bytes followed by the bytes themselves is returned. On error a negative status code will be returned.
Example
$ pigs fr 0 10
5 48 49 128 144 255
$ pigs fr 0 10
0
The number of bytes to move is num. Positive offsets move forward, negative offsets backwards. The move start position is determined by from as follows.
From 0 start 1 current position 2 end
Upon success the new byte position within the file (>=0) is returned. On error a negative status code will be returned.
Example
$ pigs fs 0 200 0 # Seek to start of file plus 200
200
$ pigs fs 0 0 1 # Return current position
200
$ pigs fs 0 0 2 # Seek to end of file, return size
296235
Upon success nothing is returned. On error a negative status code will be returned.
Example
$ pigs fw 0 23 45 67 89
This command returns the PWM dutycycle in use on GPIO u.
Upon success the dutycycle is returned. On error a negative status code will be returned.
For normal PWM the dutycycle will be out of the defined range for the GPIO (see PRG).
If a hardware clock is active on the GPIO the reported dutycycle will be 500000 (500k) out of 1000000 (1M).
If hardware PWM is active on the GPIO the reported dutycycle will be out of a 1000000 (1M).
Example
$ pigs p 4 129
$ pigs gdc 4
129
pigs gdc 5
-92
ERROR: GPIO is not in use for PWM
This command returns the servo pulsewidth in use on GPIO u.
Upon success the servo pulsewidth is returned. On error a negative status code will be returned.
Example
$ pigs s 4 1235
$ pigs gpw 4
1235
$ pigs gpw 9
-93
ERROR: GPIO is not in use for servo pulses
Example
$ pigs h
$ pigs help
Upon success nothing is returned. On error a negative status code will be returned.
Example
$ pigs hc 4 5000 # start a 5 KHz clock on GPIO 4 (clock 0)
$ pigs hc 5 5000000 # start a 5 MHz clcok on GPIO 5 (clock 1)
-99
ERROR: need password to use hardware clock 1
The same clock is available on multiple GPIO. The latest frequency setting will be used by all GPIO which share a clock.
The GPIO must be one of the following.
4 clock 0 All models
5 clock 1 All models but A and B (reserved for system use)
6 clock 2 All models but A and B
20 clock 0 All models but A and B
21 clock 1 All models but A and B Rev.2 (reserved for system use)
32 clock 0 Compute module only
34 clock 0 Compute module only
42 clock 1 Compute module only (reserved for system use)
43 clock 2 Compute module only
44 clock 1 Compute module only (reserved for system use)
Access to clock 1 is protected by a password as its use will likely crash the Pi. The password is given by or'ing 0x5A000000 with the GPIO number.
NOTE: Any waveform started by WVTX, WVTXR, or WVCHA will be cancelled.
This function is only valid if the pigpio main clock is PCM. The main clock defaults to PCM but may be overridden when the pigpio daemon is started (option -t).
Upon success nothing is returned. On error a negative status code will be returned.
$ pigs hp 18 100 800000 # 80% dutycycle
$ pigs hp 19 100 200000 # 20% dutycycle
$ pigs hp 19 400000000 100000
-96
ERROR: invalid hardware PWM frequency
The same PWM channel is available on multiple GPIO. The latest frequency and dutycycle setting will be used by all GPIO which share a PWM channel.
The GPIO must be one of the following.
12 PWM channel 0 All models but A and B
13 PWM channel 1 All models but A and B
18 PWM channel 0 All models
19 PWM channel 1 All models but A and B
40 PWM channel 0 Compute module only
41 PWM channel 1 Compute module only
45 PWM channel 1 Compute module only
52 PWM channel 0 Compute module only
53 PWM channel 1 Compute module only
The actual number of steps beween off and fully on is the integral part of 250M/pf (375M/pf for the BCM2711).
The actual frequency set is 250M/steps (375M/steps for the BCM2711).
There will only be a million steps for a pf of 250 (375 for the BCM2711). Lower frequencies will have more steps and higher frequencies will have fewer steps. pdc is automatically scaled to take this into account.
The hardware revision is found in the last 4 characters on the revision line of /proc/cpuinfo.
If the hardware revision can not be found or is not a valid hexadecimal number the command returns 0.
The revision number can be used to determine the assignment of GPIO to pins (see g).
There are currently three types of board.
Type 1 boards have hardware revision numbers of 2 and 3.
Type 2 boards have hardware revision numbers of 4, 5, 6, and 15.
Type 3 boards have hardware revision numbers of 16 or greater.
for "Revision : 0002" the command returns 2.
for "Revision : 000f" the command returns 15.
for "Revision : 000g" the command returns 0.
Example
$ pigs hwver # On a B+
16
Upon success nothing is returned. On error a negative status code will be returned.
Example
$ pigs i2cc 0 # First close okay.
$ pigs i2cc 0 # Second fails.
-25
ERROR: unknown handle
Physically buses 0 and 1 are available on the Pi. Higher numbered buses will be available if a kernel supported bus multiplexor is being used.
The GPIO used are given in the following table.
SDA SCL I2C 0 0 1 I2C 1 2 3
No flags are currently defined. The parameter if should be 0.
Upon success the next free handle (>=0) is returned. On error a negative status code will be returned.
Example
$ pigs i2co 1 0x70 0 # Bus 1, device 0x70, flags 0.
0
$ pigs i2co 1 0x53 0 # Bus 1, device 0x53, flags 0.
1
Upon success a value between 0 and 65535 will be returned. On error a negative status code will be returned.
Example
$ pigs i2cpc 0 37 43210
39933
$ pigs i2cpc 0 256 43210
ERROR: bad i2c/spi/ser parameter
-81
This command writes the data bytes bvs to register r of the I2C device associated with handle h and returns a device specific number of bytes.
Upon success the count of returned bytes followed by the bytes themselves is returned. On error a negative status code will be returned.
Example
$ pigs i2cpk 0 0 0x11 0x12
6 0 0 0 0 0 0
This command returns a single byte read from register r of the I2C device associated with handle h.
Upon success a value between 0 and 255 will be returned. On error a negative status code will be returned.
Example
$ pigs i2crb 0 0
6
This command returns num bytes read from the I2C device associated with handle h.
Upon success the count of returned bytes followed by the bytes themselves is returned. On error a negative status code will be returned.
This command operates on the raw I2C device. The maximum value of the parameter num is dependent on the I2C drivers and the device itself. pigs imposes a limit of about 8000 bytes.
Example
$ pigs i2crd 0 16
16 6 24 0 0 0 0 0 0 0 0 0 0 0 0 32 78
This command returns num bytes from register r of the I2C device associated with handle h.
Upon success the count of returned bytes followed by the bytes themselves is returned. On error a negative status code will be returned.
The parameter num may be 1-32.
Example
$ pigs i2cri 0 0 16
16 237 155 155 155 155 155 155 155 155 155 155 155 155 155 155 155
This command returns between 1 and 32 bytes read from register r of the I2C device associated with handle h.
Upon success the count of returned bytes followed by the bytes themselves is returned. On error a negative status code will be returned.
The number of bytes of returned data is specific to the device and register.
Example
$ pigs i2crk 0 0
6 0 0 0 0 0 0
$ pigs i2crk 0 1
24 0 0 0 0 0 0 0 0 0 0 0 0 120 222 105 215 128 87 195 217 0 0 0 0
This command returns a single byte read from the I2C device associated with handle h.
Upon success a value between 0 and 255 will be returned. On error a negative status code will be returned.
Example
$ pigs i2crs 0
0
This command returns a single 16 bit word read from register r of the I2C device associated with handle h.
Upon success a value between 0 and 65535 will be returned. On error a negative status code will be returned.
Example
$ pigs i2crw 0 0
6150
This command writes a single byte bv to register r of the I2C device associated with handle h.
Upon success nothing is returned. On error a negative status code will be returned.
Example
$ pigs i2cwb 0 10 0x54
This command writes a block of bytes bvs to the I2C device associated with handle h.
Upon success nothing is returned. On error a negative status code will be returned.
The number of bytes which may be written in one transaction is dependent on the I2C drivers and the device itself. pigs imposes a limit of about 500 bytes.
This command operates on the raw I2C device.
Example
$ pigs i2cwd 0 0x01 0x02 0x03 0x04
This command writes between 1 and 32 bytes bvs to register r of the I2C device associated with handle h.
Upon success nothing is returned. On error a negative status code will be returned.
Example
$ pigs i2cwi 0 4 0x01 0x04 0xc0
This command writes between 1 and 32 bytes bvs to register r of the I2C device associated with handle h.
Upon success nothing is returned. On error a negative status code will be returned.
Example
pigs i2cwk 0 4 0x01 0x04 0xc0
This command writes a single bit to the I2C device associated with handle h.
Upon success nothing is returned. On error a negative status code will be returned.
Example
$ pigs i2cwq 0 1
This command writes a single byte bv to the I2C device associated with handle h.
Upon success nothing is returned. On error a negative status code will be returned.
Example
$ pigs i2cws 0 0x12
$ pigs i2cws 0 0xff
-82
ERROR: I2C write failed
This command writes a single 16 bit word wv to register r of the I2C device associated with handle h.
Upon success nothing is returned. On error a negative status code will be returned.
Example
$ pigs i2cww 0 0 0xffff
The following command codes are supported:
Name Cmd & Data Meaning
End 0 No more commands
Escape 1 Next P is two bytes
On 2 Switch combined flag on
Off 3 Switch combined flag off
Address 4 P Set I2C address to P
Flags 5 lsb msb Set I2C flags to lsb + (msb << 8)
Read 6 P Read P bytes of data
Write 7 P ... Write P bytes of data
The address, read, and write commands take a parameter P. Normally P is one byte (0-255). If the command is preceded by the Escape command then P is two bytes (0-65535, least significant byte first).
The address defaults to that associated with the handle h. The flags default to 0. The address and flags maintain their previous value until updated.
Example
Set address 0x53, write 0x32, read 6 bytes
Set address 0x1E, write 0x03, read 6 bytes
Set address 0x68, write 0x1B, read 8 bytes
End
0x04 0x53 0x07 0x01 0x32 0x06 0x06
0x04 0x1E 0x07 0x01 0x03 0x06 0x06
0x04 0x68 0x07 0x01 0x1B 0x06 0x08
0x00
This command sets GPIO g to mode m, typically input (read) or output (write).
Upon success nothing is returned. On error a negative status code will be returned.
Each GPIO can be configured to be in one of 8 different modes. The modes are named Input, Output, ALT0, ALT1, ALT2, ALT3, ALT4, and ALT5.
To set the mode use the code for the mode.
Mode Input Output ALT0 ALT1 ALT2 ALT3 ALT4 ALT5
Code R W 0 1 2 3 4 5
Example
$ pigs m 4 r # Input (read)
$ pigs m 4 w # Output (write)
$ pigs m 4 0 # ALT 0
$ pigs m 4 5 # ALT 5
This command returns the current mode of GPIO g.
Upon success the value of the GPIO mode is returned. On error a negative status code will be returned.
Value 0 1 2 3 4 5 6 7
Mode Input Output ALT5 ALT4 ALT0 ALT1 ALT2 ALT3
Example
$ pigs mg 4
1
Upon success nothing is returned. On error a negative status code will be returned.
The main use of this command is expected to be within Scripts.
Example
$ pigs mics 20 # Delay 20 microseconds.
$ pigs mics 1000000 # Delay 1 second.
$ pigs mics 2000000
-64
ERROR: bad MICS delay (too large)
This command delays execution for v milliseconds.
Upon success nothing is returned. On error a negative status code will be returned.
Example
$ pigs mils 2000 # Delay 2 seconds.
$ pigs mils 61000
-65
ERROR: bad MILS delay (too large)
This command starts notifications on handle h returned by a prior call to NO.
Upon success nothing is returned. On error a negative status code will be returned.
The notification gets state changes for each GPIO specified by bits.
Example
$ pigs nb 0 -1 # Shorthand for GPIO 0-31.
$ pigs nb 0 0xf0 # Get notifications for GPIO 4-7.
$ pigs nb 1 0xf
-25
ERROR: unknown handle
This command stops notifications on handle h returned by a prior call to NO and releases the handle for reuse.
Upon success nothing is returned. On error a negative status code will be returned.
Example
$ pigs nc 0 # First call succeeds.
$ pigs nc 1 # Second call fails.
-25
ERROR: unknown handle
This command requests a free notification handle.
A notification is a method for being notified of GPIO state changes via a pipe.
Upon success the command returns a handle greater than or equal to zero. On error a negative status code will be returned.
Notifications for handle x will be available at the pipe named /dev/pigpiox (where x is the handle number).
E.g. if the command returns 15 then the notifications must be read from /dev/pigpio15.
Example
$ pigs no
0
This command pauses notifications on handle h returned by a prior call to NO.
Upon success nothing is returned. On error a negative status code will be returned.
Notifications for the handle are suspended until a new NB command is given for the handle.
Example
$ pigs np 0
This command starts PWM on GPIO u with dutycycle v. The dutycycle varies from 0 (off) to range (fully on). The range defaults to 255.
Upon success nothing is returned. On error a negative status code will be returned.
This and the servo functionality use the DMA and PWM or PCM peripherals to control and schedule the pulsewidths and dutycycles.
The PRS command may be used to change the default range of 255.
Example
$ pigs p 4 64 # Start PWM on GPIO 4 with 25% dutycycle
$ pigs p 4 128 # 50%
$ pigs p 4 192 # 75%
$ pigs p 4 255 # 100%
This command gets the pad drive strength padma in mA.
Returns the pad drive strength if OK. On error a negative status code will be returned.
Pad GPIO
0 0-27
1 28-45
2 46-53
Example
$ pigs padg 0
8
$ pigs pads 0 16
$ pigs padg 0
16
pigs padg 3
-126
ERROR: bad pad number
This command sets the pad drive strength padma in mA.
Upon success nothing is returned. On error a negative status code will be returned.
Pad GPIO
0 0-27
1 28-45
2 46-53
Example
$ pigs pads 0 16
$ pigs padg 0
16
$ pigs pads 0 17
-127
ERROR: bad pad drive strength
Validates the text t of a script without storing the script.
Upon success nothing is returned. On error a list of detected script errors will be given.
See Scripts.
This command may be used to find script syntax faults.
Example
$ pigs parse tag 100 w 22 1 mils 200 w 22 0 mils 800 jmp 100
$ pigs parse tag 0 w 22 1 mills 50 w 22 0 dcr p10 jp 99
Unknown command: mills
Unknown command: 50
Bad parameter to dcr
Can't resolve tag 99
This command returns the PWM frequency in Hz used for GPIO u.
Upon success the PWM frequency is returned. On error a negative status code will be returned.
For normal PWM the frequency will be that defined for the GPIO by PFS.
If a hardware clock is active on the GPIO the reported frequency will be that set by HC.
If hardware PWM is active on the GPIO the reported frequency will be that set by HP.
Example
$ pigs pfg 4
800
$ pigs pfg 34
ERROR: GPIO not 0-31
-2
The numerically closest frequency to v will be selected.
Upon success the new frequency is returned. On error a negative status code will be returned.
If PWM is currently active on the GPIO it will be switched off and then back on at the new frequency.
Each GPIO can be independently set to one of 18 different PWM frequencies.
The selectable frequencies depend upon the sample rate which may be 1, 2, 4, 5, 8, or 10 microseconds (default 5). The sample rate is set when the pigpio daemon is started.
The frequencies for each sample rate are:
Hertz
1: 40000 20000 10000 8000 5000 4000 2500 2000 1600
1250 1000 800 500 400 250 200 100 50
2: 20000 10000 5000 4000 2500 2000 1250 1000 800
625 500 400 250 200 125 100 50 25
4: 10000 5000 2500 2000 1250 1000 625 500 400
313 250 200 125 100 63 50 25 13
sample
rate
(us) 5: 8000 4000 2000 1600 1000 800 500 400 320
250 200 160 100 80 50 40 20 10
8: 5000 2500 1250 1000 625 500 313 250 200
156 125 100 63 50 31 25 13 6
10: 4000 2000 1000 800 500 400 250 200 160
125 100 80 50 40 25 20 10 5
Example
pigs pfs 4 0 # 0 selects the lowest frequency.
10
$ pigs pfs 4 1000 # Set 1000Hz PWM.
1000
$ pigs pfs 4 100000 # Very big number selects the highest frequency.
8000
This command returns the pigpio library version.
Example
$ pigs pigpv
17
This command returns the dutycycle range for GPIO u.
Upon success the range is returned. On error a negative status code will be returned.
If a hardware clock or hardware PWM is active on the GPIO the reported range will be 1000000 (1M).
Example
$ pigs prg 4
255
This command stores a script t for later execution.
If the script is valid a script id (>=0) is returned which is passed to the other script commands. On error a negative status code will be returned.
See Scripts.
Example
$ pigs proc tag 123 w 4 0 mils 200 w 4 1 mils 300 dcr p0 jp 123
0
$ pigs proc tag 123 w 4 0 mils 5 w 4 1 mils 5 jmp 12
ERROR: script has unresolved tag
-63
This command deletes script sid.
Upon success nothing is returned. On error a negative status code will be returned.
See Scripts.
Example
$ pigs procd 1
$ pigs procd 1
ERROR: unknown script id
-48
This command returns the status of script sid as well as the current value of its 10 parameters.
Upon success the script status and parameters are returned. On error a negative status code will be returned.
The script status may be one of
0 being initialised
1 halted
2 running
3 waiting
4 failed
See Scripts.
Example
$ pigs procp 0
1 0 0 0 0 0 0 0 0 0 0
This command runs stored script sid passing it up to 10 optional parameters.
Upon success nothing is returned. On error a negative status code will be returned.
See Scripts.
Example
$ pigs proc tag 123 w 4 0 mils 200 w 4 1 mils 300 dcr p0 jp 123
0
$ pigs procr 0 50 # Run script 0 with parameter 0 of 50.
$ pigs procp 0
2 44 0 0 0 0 0 0 0 0 0
$ pigs procp 0
2 37 0 0 0 0 0 0 0 0 0
$ pigs procp 0
2 10 0 0 0 0 0 0 0 0 0
$ pigs procp 0
2 5 0 0 0 0 0 0 0 0 0
$ pigs procp 0
2 2 0 0 0 0 0 0 0 0 0
$ pigs procp 0
1 -1 0 0 0 0 0 0 0 0 0
This command stops a running script sid.
Upon success nothing is returned. On error a negative status code will be returned.
See Scripts.
Example
$ pigs procs 0
$ pigs procs 1
-48
ERROR: unknown script id
This command sets the parameters of a stored script sid passing it up to 10 parameters.
Upon success nothing is returned. On error a negative status code will be returned.
See Scripts.
Example
$ pigs proc tag 0 hp 18 p0 p1 mils 1000 jmp 0
0
$ pigs procu 0 50 500000
$ pigs procr 0
$ pigs procu 0 100
$ pigs procu 0 200
$ pigs procu 0 200 100000
This command returns the real underlying range used by GPIO u.
If a hardware clock is active on the GPIO the reported real range will be 1000000 (1M).
If hardware PWM is active on the GPIO the reported real range will be approximately 250M divided by the set PWM frequency.
On error a negative status code will be returned.
See PRS.
Example
$ pigs prrg 17
250
$ pigs pfs 17 0
10
$ pigs prrg 17
20000
$ pigs pfs 17 100000
8000
$ pigs prrg 17
25
This command sets the dutycycle range v to be used for GPIO u. Subsequent uses of command P/PWM will use a dutycycle between 0 (off) and v (fully on).
Upon success the real underlying range used by the GPIO is returned. On error a negative status code will be returned.
If PWM is currently active on the GPIO its dutycycle will be scaled to reflect the new range.
The real range, the number of steps between fully off and fully on for each frequency, is given in the following table.
#1 #2 #3 #4 #5 #6 #7 #8 #9
25 50 100 125 200 250 400 500 625
#10 #11 #12 #13 #14 #15 #16 #17 #18 800 1000 1250 2000 2500 4000 5000 10000 20000
The real value set by PRS is (dutycycle * real range) / range.
See PRRG
Example
$ pigs prs 18 1000
250
This command sets the internal pull/up down for GPIO g to mode p.
Upon success nothing is returned. On error a negative status code will be returned.
The mode may be pull-down (D), pull-up (U), or off (O).
Example
$ pigs pud 4 d # Set pull-down on GPIO 4.
$ pigs pud 4 u # Set pull-up on GPIO 4.
$ pigs pud 4 o # No pull-up/down on GPIO 4.
This reads the current level of GPIO g.
Upon success the current level is returned. On error a negative status code will be returned.
Example
$ pigs r 17 # Get level of GPIO 17.
0
$ pigs r 4 # Get level of GPIO 4.
1
This command starts servo pulses of v microseconds on GPIO u.
Upon success nothing is returned. On error a negative status code will be returned.
The servo pulsewidth may be 0 (off), 500 (most anti-clockwise) to 2500 (most clockwise).
The range supported by servos varies and should probably be determined by experiment. Generally values between 1000-2000 should be safe. A value of 1500 should always be safe and represents the mid-point of rotation.
You can DAMAGE a servo if you command it to move beyond its limits.
Example
$ pigs SERVO 17 1500
This example causes an on pulse of 1500 microseconds duration to be transmitted on GPIO 17 at a rate of 50 times per second.
This will command a servo connected to GPIO 17 to rotate to its mid-point.
Example
pigs s 17 0 # Switch servo pulses off.
This command closes a serial handle h previously opened with SERO.
Upon success nothing is returned. On error a negative status code will be returned.
Example
$ pigs serc 0 # First close okay.
$ pigs serc 0 # Second close gives error.
-25
ERROR: unknown handle
This command returns the number of bytes of data available to be read from the serial device associated with handle h.
Upon success the count of bytes available to be read is returned (which may be 0). On error a negative status code will be returned.
Example
$ pigs serda 0
0
This command opens the serial dev at b bits per second.
No flags are currently defined. sef should be set to zero.
Upon success a handle (>=0) is returned. On error a negative status code will be returned.
The device name must start with /dev/tty or /dev/serial.
The baud rate must be one of 50, 75, 110, 134, 150, 200, 300, 600, 1200, 1800, 2400, 4800, 9600, 19200, 38400, 57600, 115200, or 230400.
Example
$ pigs sero /dev/ttyAMA0 9600 0
0
$ pigs sero /dev/tty1 38400 0
1
This command returns up to num bytes of data read from the serial device associated with handle h.
Upon success the count of returned bytes followed by the bytes themselves is returned. On error a negative status code will be returned.
Example
$ pigs serr 0 10
5 48 49 128 144 255
$ pigs serr 0 10
0
This command returns a byte of data read from the serial device associated with handle h.
Upon success a number between 0 and 255 is returned. On error a negative status code will be returned.
Example
$ pigs serrb 0
23
$ pigs serrb 0
45
This command writes bytes bvs to the serial device associated with handle h.
Upon success nothing is returned. On error a negative status code will be returned.
Example
$ pigs serw 0 23 45 67 89
This command writes a single byte bv to the serial device associated with handle h.
Upon success nothing is returned. On error a negative status code will be returned.
Example
$ pigs serwb 0 23
$ pigs serwb 0 0xf0
This command uses the system call to execute a shell script name with the given string str as its parameter.
The exit status of the system call is returned if OK, otherwise PI_BAD_SHELL_STATUS.
name must exist in /opt/pigpio/cgi and must be executable.
The returned exit status is normally 256 times that set by the shell script exit function. If the script can't be found 32512 will be returned.
The following table gives some example returned statuses.
Script exit status Returned system call status
1 256
5 1280
10 2560
200 51200
script not found 32512
Example
# pass two parameters, hello and world
$ pigs shell scr1 hello world
256
# pass three parameters, hello, string with spaces, and world
$ pigs shell scr1 "hello 'string with spaces' world"
256
# pass one parameter, hello string with spaces world
$ pigs shell scr1 "
256
# non-existent script
$ pigs shell scr78 par1
32512
This command returns up to num bytes of bit bang serial data read from GPIO u.
Upon success the count of returned bytes followed by the bytes themselves is returned. On error a negative status code will be returned.
The GPIO u should have been initialised with the SLRO command.
The bytes returned for each character depend upon the number of data bits db specified in the SLRO command.
For db 1-8 there will be one byte per character.
For db 9-16 there will be two bytes per character.
For db 17-32 there will be four bytes per character.
Example
$ pigs slr 15 20
6 1 0 23 45 89 0
This command closes GPIO u for reading bit bang serial data.
Upon success nothing is returned. On error a negative status code will be returned.
Example
$ pigs slrc 23
$ pigs slrc 23
-38
ERROR: no serial read in progress on GPIO
This command sets the logic level for reading bit bang serial data on GPIO u.
Upon success nothing is returned. On error a negative status code will be returned.
The invert parameter v is 1 for inverted signal, 0 for normal.
Example
$ pigs slri 17 1 # invert logic on GPIO 17
$ pigs slri 23 0 # use normal logic on GPIO 23
This command opens GPIO u for reading bit bang serial data at b baud and db data bits.
Upon success nothing is returned. On error a negative status code will be returned.
The baud rate may be between 50 and 250000 bits per second.
The received data is held in a cyclic buffer.
It is the user's responsibility to read the data (with SLR) in a timely fashion.
Example
$ pigs slro 23 19200 8
$ pigs slro 23 19200 8
-50
ERROR: GPIO already in use
This command closes the SPI handle h returned by a prior call to SPIO.
Upon success nothing is returned. On error a negative status code will be returned.
Example
$ pigs spic 1
$ pigs spic 1
-25
ERROR: unknown handle
This command returns a handle to a SPI device on channel c.
Data will be transferred at b bits per second. The flags spf may be used to modify the default behaviour of 4-wire operation, mode 0, active low chip select.
Speeds between 32kbps and 125Mbps are allowed. Speeds above 30Mbps are unlikely to work.
The Pi has two SPI peripherals: main and auxiliary.
The main SPI has two chip selects (channels), the auxiliary has three.
The auxiliary SPI is available on all models but the A and B.
The GPIO used are given in the following table.
MISO MOSI SCLK CE0 CE1 CE2 Main SPI 9 10 11 8 7 - Aux SPI 19 20 21 18 17 16
The flags consists of the least significant 22 bits.
21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
b b b b b b R T n n n n W A u2 u1 u0 p2 p1 p0 m m
mm defines the SPI mode.
Warning: modes 1 and 3 do not appear to work on the auxiliary SPI.
Mode POL PHA
0 0 0
1 0 1
2 1 0
3 1 1
px is 0 if CEx is active low (default) and 1 for active high.
ux is 0 if the CEx GPIO is reserved for SPI (default) and 1 otherwise.
A is 0 for the main SPI, 1 for the auxiliary SPI.
W is 0 if the device is not 3-wire, 1 if the device is 3-wire. Main SPI only.
nnnn defines the number of bytes (0-15) to write before switching the MOSI line to MISO to read data. This field is ignored if W is not set. Main SPI only.
T is 1 if the least significant bit is transmitted on MOSI first, the default (0) shifts the most significant bit out first. Auxiliary SPI only.
R is 1 if the least significant bit is received on MISO first, the default (0) receives the most significant bit first. Auxiliary SPI only.
bbbbbb defines the word size in bits (0-32). The default (0) sets 8 bits per word. Auxiliary SPI only.
The SPIR, SPIW, and SPIX commands transfer data packed into 1, 2, or 4 bytes according to the word size in bits.
For bits 1-8 there will be one byte per character.
For bits 9-16 there will be two bytes per character.
For bits 17-32 there will be four bytes per character.
Multi-byte transfers are made in least significant byte first order.
E.g. to transfer 32 11-bit words 64 bytes need to be sent.
E.g. to transfer the 14 bit value 0x1ABC send the bytes 0xBC followed by 0x1A.
The other bits in flags should be set to zero.
Upon success a handle (>=0) is returned. On error a negative status code will be returned.
Example
$ pigs spio 0 100000 3 # Open channel 0 at 100kbps in mode 3.
0
$ pigs spio 0 32000 256 # Open channel 0 of auxiliary spi at 32kbps.
1
This command returns num bytes read from the SPI device associated with handle h.
Upon success the count of returned bytes followed by the bytes themselves is returned. On error a negative status code will be returned.
Example
$ pigs spir 0 10 # Read 10 bytes from the SPI device.
10 0 0 0 0 0 0 0 0 0 0
This command writes bytes bvs to the SPI device associated with handle h.
Upon success nothing is returned. On error a negative status code will be returned.
Example
$ pigs spiw 0 0x22 0x33 0xcc 0xff
This command writes bytes bvs to the SPI device associated with handle h. It returns the same number of bytes read from the device.
Upon success the count of returned bytes followed by the bytes themselves is returned. On error a negative status code will be returned.
Example
$ pigs spix 0 0x22 0x33 0xcc 0xff
4 0 0 0 0
This command returns the current system tick.
Tick is the number of microseconds since system boot.
As tick is an unsigned 32 bit quantity it wraps around after 2^32 microseconds, which is approximately 1 hour 12 minutes.
Example
$ pigs t mils 1000 t
3691823946
3692833987
This command sends a trigger pulse of pl microseconds at level L to GPIO u.
Upon success nothing is returned. On error a negative status code will be returned.
The GPIO is set to not level at the end of the pulse.
Example
$ pigs trig 4 10 1
$ pigs trig 4 51 1
-46
ERROR: trigger pulse > 50 microseconds
This command sets GPIO g to level L. The level may be 0 (low, off, clear) or 1 (high, on, set).
Upon success nothing is returned. On error a negative status code will be returned.
Example
$ pigs w 23 0
$ pigs w 23 1
$ pigs w 23 2
-5
ERROR: level not 0-1
This command sets a watchdog of v milliseconds on GPIO u.
Upon success nothing is returned. On error a negative status code will be returned.
The watchdog is nominally in milliseconds.
One watchdog may be registered per GPIO.
The watchdog may be cancelled by setting timeout to 0.
Once a watchdog has been started monitors of the GPIO will be triggered every timeout interval after the last GPIO activity. The watchdog expiry will be indicated by a special TIMEOUT value.
Example
$ pigs wdog 23 90000
-15
ERROR: timeout not 0-60000
$ pigs wdog 23 9000
This example causes a report to be written to any notification pipes listening on GPIO 23 whenever GPIO 23 changes state or approximately every 9000 ms.
This command adds 1 one or more triplets trips of GPIO on, GPIO off, delay to the existing waveform (if any).
Upon success the total number of pulses in the waveform so far is returned. On error a negative status code will be returned.
The triplets will be added at the start of the existing waveform. If they are to start offset from the start then the first triplet should consist solely of a delay i.e. 0 0 offset.
Example
$ pigs wvag 0x10 0x80 1000 0x80 0x10 9000
2
$ pigs wvag 0 0 10000 0x10 0x80 1000 0x80 0x10 9000
4
This command adds a waveform representing serial data bvs to GPIO u at b baud to the existing waveform (if any). The serial data starts o microseconds from the start of the waveform.
Upon success the total number of pulses in the waveform so far is returned. On error a negative status code will be returned.
The serial data is formatted as one start bit, db data bits, and sb/2 stop bits.
The baud rate may be between 50 and 1000000 bits per second.
It is legal to add serial data streams with different baud rates to the same waveform.
The bytes required for each character depend upon db.
For db 1-8 there will be one byte per character.
For db 9-16 there will be two bytes per character.
For db 17-32 there will be four bytes per character.
Example
$ pigs wvas 4 9600 8 2 0 0x30 0x31 0x32 0x33
23
$ pigs wvas 7 38400 8 2 0 0x41 0x42
35
This command returns the id of the waveform currently being transmitted. Chained waves are not supported.
Returns the waveform id or one of the following special values:
9998 - transmitted wave not found
9999 - no wave being transmitted
Example
$ pigs wvtat
9999
This command checks to see if a waveform is currently being transmitted.
Returns 1 if a waveform is currently being transmitted, otherwise 0.
Example
$ pigs wvbsy
0
This command transmits a chain of waveforms.
NOTE: Any hardware PWM started by HP will be cancelled.
The waves to be transmitted are specified by the contents of bvs which contains an ordered list of wave_ids and optional command codes and related data.
Upon success 0 is returned. On error a negative status code will be returned.
Each wave is transmitted in the order specified. A wave may occur multiple times per chain.
A blocks of waves may be transmitted multiple times by using the loop commands. The block is bracketed by loop start and end commands. Loops may be nested.
Delays between waves may be added with the delay command.
The following command codes are supported:
Name Cmd & Data Meaning
Loop Start 255 0 Identify start of a wave block
Loop Repeat 255 1 x y loop x + y*256 times
Delay 255 2 x y delay x + y*256 microseconds
Loop Forever 255 3 loop forever
If present Loop Forever must be the last entry in the chain.
The code is currently dimensioned to support a chain with roughly 600 entries and 20 loop counters.
Example
#!/bin/bash
GPIO=4
WAVES=5
pigs m $GPIO w
for ((i=0; i<$WAVES; i++))
do
pigs wvag $((1<<GPIO)) 0 20 0 $((1<<GPIO)) $(((i+1)*200))
w[i]=$(pigs wvcre)
done
# transmit waves 4+3+2
# loop start
# transmit waves 0+0+0
# loop start
# transmit waves 0+1
# delay 5000us
# loop end (repeat 30 times)
# loop start
# transmit waves 2+3+0
# transmit waves 3+1+2
# loop end (repeat 10 times)
# loop end (repeat 5 times)
# transmit waves 4+4+4
# delay 20000us
# transmit waves 0+0+0
pigs wvcha .br
${w[4]} ${w[3]} ${w[2]} .br
255 0 .br
${w[0]} ${w[0]} ${w[0]} .br
255 0 .br
${w[0]} ${w[1]} .br
255 2 0x88 0x13 .br
255 1 30 0 .br
255 0 .br
${w[2]} ${w[3]} ${w[0]} .br
${w[3]} ${w[1]} ${w[2]} .br
255 1 10 0 .br
255 1 5 0 .br
${w[4]} ${w[4]} ${w[4]} .br
255 2 0x20 0x4E .br
${w[0]} ${w[0]} ${w[0]}
while [[ $(pigs wvbsy) -eq 1 ]]; do sleep 0.1; done
for ((i=0; i<$WAVES; i++)); do echo ${w[i]}; pigs wvdel ${w[i]}; done
This command clears all waveforms.
Nothing is returned.
Example
$ pigs wvclr
This command creates a waveform from the data provided by the prior calls to the WVAG and WVAS commands.
Upon success a wave id (>=0) is returned. On error a negative status code will be returned.
The data provided by the WVAG and WVAS commands is consumed by this command.
As many waveforms may be created as there is space available. The wave id is passed to WVTX or WVTXR to specify the waveform to transmit.
Normal usage would be
Step 1. WVCLR to clear all waveforms and added data.
Step 2. WVAG/WVAS calls to supply the waveform data.
Step 3. WVCRE to create the waveform and get a unique id.
Repeat steps 2 and 3 as needed.
Step 4. WVTX or WVTXR with the id of the waveform to transmit.
A waveform comprises of one or more pulses.
A pulse specifies
1) the GPIO to be switched on at the start of the pulse.
2) the GPIO to be switched off at the start of the pulse.
3) the delay in microseconds before the next pulse.
Any or all the fields can be zero. It doesn't make any sense to set all the fields to zero (the pulse will be ignored).
When a waveform is started each pulse is executed in order with the specified delay between the pulse and the next.
Example
$ pigs wvas 4 9600 0 23 45 67 89 90
37
$ pigs wvcre
0
$ pigs wvcre
-69
ERROR: attempt to create an empty waveform
Create a waveform of fixed size. Similar to WVCRE, this command creates a waveform but pads the consumed resources to a fixed size, specified as a percent of the total resources. Padded waves of equal size can be re-cycled efficiently allowing newly created waves to re-use the resources of deleted waves of the same dimension.
Upon success a wave id (>=0) is returned. On error a negative status code will be returned.
The data provided by the WVAG and WVAS commands are consumed by this command.
As many waveforms may be created as there is space available. The wave id is passed to WVTX or WVTXR to specify the waveform to transmit.
Normal usage would be
Step 1. WVCLR to clear all waveforms and added data.
Step 2. WVAG/WVAS calls to supply the waveform data.
Step 3. WVCAP to create a waveform of a uniform size.
Step 4. WVTX or WVTXR with the id of the waveform to transmit.
Repeat steps 2 - 4 as needed.
Step 5. Any wave id can now be deleted and another wave of the same size can be created in its place.
Example
Example
# Create a wave that consumes 50% of the total resource:
$ pigs wvag 16 0 5000000 0 16 5000000
2
$ pigs wvcap 50
0
$ pigs wvtx 0
11918
This command deletes the waveform with id wid.
The wave is flagged for deletion. The resources used by the wave will only be reused when either of the following apply.
- all waves with higher numbered wave ids have been deleted or have been flagged for deletion.
- a new wave is created which uses exactly the same resources as the current wave (see the C source for gpioWaveCreate for details).
Upon success nothing is returned. On error a negative status code will be returned.
Example
$ pigs wvdel 0
$ pigs wvdel 0
-66
ERROR: non existent wave id
This command aborts the transmission of the current waveform.
Nothing is returned.
This command is intended to stop a waveform started in the repeat mode.
Example
$ pigs wvhlt
This clears any existing waveform data ready for the creation of a new waveform.
Nothing is returned.
Example
$ pigs wvnew
The statistic requested by ws is returned.
ws identifies the subcommand as follows.
0 Get Cbs
1 Get High Cbs
2 Get Max Cbs
Example
$ pigs wvas 4 9600 0 23 45 67 89 90
37
$ pigs wvsc 0
74
$ pigs wvsc 1
74
$ pigs wvsc 2
25016
The statistic requested by ws is returned.
ws identifies the subcommand as follows.
0 Get Micros
1 Get High Micros
2 Get Max Micros
Example
$ pigs wvsm 0
5314
$ pigs wvsm 1
5314
$ pigs wvsm 2
1800000000
The statistic requested by ws is returned.
ws identifies the subcommand as follows.
0 Get Pulses
1 Get High Pulses
2 Get Max Pulses
Example
$ pigs wvsp 0
37
$ pigs wvsp 1
37
$ pigs wvsp 2
12000
This command transmits the waveform with id wid once.
NOTE: Any hardware PWM started by HP will be cancelled.
Upon success the number of DMA control blocks in the waveform is returned. On error a negative status code will be returned.
Example
$ pigs wvtx 1
75
$ pigs wvtx 2
-66
ERROR: non existent wave id
This command transmits the waveform with id wid using mode wmde.
The mode may be send once (0), send repeatedly (1), send once but first sync with previous wave (2), or send repeatedly but first sync with previous wave (3).
WARNING: bad things may happen if you delete the previous waveform before it has been synced to the new waveform.
NOTE: Any hardware PWM started by HP will be cancelled.
Upon success the number of DMA control blocks in the waveform is returned. On error a negative status code will be returned.
Example
$ pigs wvtxm 1 3
75
$ pigs wvtxm 2 0
-66
ERROR: non existent wave id
This command transmits the waveform with id wid repeatedly.
NOTE: Any hardware PWM started by HP will be cancelled.
Upon success the number of DMA control blocks in the waveform is returned. On error a negative status code will be returned.
Example
$ pigs wvtxr 1
75
$ pigs wvtxr 2
-66
ERROR: non existent wave id
The number of microseconds level changes are reported for once a noise filter has been triggered (by stdy microseconds of a stable level).
E.g. a mask of 6 (binary 110) select GPIO 1 and 2, a mask of 0x103 (binary 100000011) selects GPIO 0, 1, and 8.
/dev/ttyAMA0
/dev/ttyUSB0
/dev/tty0
/dev/serial0
From 0 start 1 current position 2 end
There are 54 General Purpose Input Outputs (GPIO) named gpio0 through gpio53.
They are split into two banks. Bank 1 consists of gpio0 through gpio31. Bank 2 consists of gpio32 through gpio53.
All the GPIO which are safe for the user to read and write are in bank 1. Not all GPIO in bank 1 are safe though. Type 1 boards have 17 safe GPIO. Type 2 boards have 21. Type 3 boards have 26.
See HWVER.
The user GPIO are marked with an X in the following table.
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Type 1 X X - - X - - X X X X X - - X X Type 2 - - X X X - - X X X X X - - X X Type 3 X X X X X X X X X X X X X X
16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 Type 1 - X X - - X X X X X - - - - - - Type 2 - X X - - - X X X X - X X X X X Type 3 X X X X X X X X X X X X - - - -
You are not prevented from writing to unsafe GPIO. The consequences of doing so range from no effect, to a crash, or corrupted data.
A handle is a number referencing an object opened by one of FO, I2CO, NO, SERO, SPIO.
Each GPIO can be configured to be in one of 8 different modes. The modes are named Input, Output, ALT0, ALT1, ALT2, ALT3, ALT4, and ALT5.
To set the mode use the code for the mode.
The value is returned by the mode get command.
Mode Input Output ALT0 ALT1 ALT2 ALT3 ALT4 ALT5
Code R W 0 1 2 3 4 5
Value 0 1 4 5 6 7 3 2
Value Meaning READ 1 open file for reading WRITE 2 open file for writing RW 3 open file for reading and writing
The following values can be or'd into the mode.
Value Meaning APPEND 4 All writes append data to the end of the file CREATE 8 The file is created if it doesn't exist TRUNC 16 The file is truncated
For the I2C and SPI commands the requested number of bytes will always be returned.
For the serial and file commands the smaller of the number of bytes available to be read (which may be zero) and num bytes will be returned.
Each GPIO can be configured to use or not use an internal pull up or pull down resistor. This is useful to provide a default state for inputs.
A pull up will default the input to 1 (high).
A pull down will default the input to 0 (low).
To set the pull up down state use the command character for the state.
Pull Up Down Off Pull Down Pull Up
Command Character O D U
There is no mechanism to read the pull up down state.
Pad GPIO
0 0-27
1 28-45
2 46-53
The number of microseconds level changes must be stable for before reporting the level changed (FG) or triggering the active part of a noise filter (FN).
E.g. 0x400000 0 100000 0 0x400000 900000 defines two pulses as follows
GPIO on GPIO off delay 0x400000 (GPIO 22) 0 (None) 100000 (1/10th s)
0 (None) 0x400000 (GPIO 22) 900000 (9/10th s)
A number of commands are restricted to GPIO in bank 1, in particular the PWM commands, the servo command, the watchdog command, and the notification command.
It is your responsibility to ensure that the PWM and servo commands are only used on safe GPIO.
See g
When a waveform is created it is given an id (0, 1, 2, ...).
0 = send once
1 = send repeatedly
2 = send once but first sync with previous wave
3 = send repeatedly but first sync with previous wave
0 = current value.
1 = highest value so far.
2 = maximum possible value.
Scripts are programs to be stored and executed by the pigpio daemon. They are intended to mitigate any performance problems associated with the pigpio daemon server/client model.
A trivial example might be useful. Suppose you want to toggle a GPIO on and off as fast as possible.
From the command line you could write
for ((i=0; i<1000;i++)); do pigs w 22 1 w 22 0; done
Timing that you will see it takes about 14 seconds, or roughly 70 toggles per second.
Using the pigpio Python module you could use code such as
#!/usr/bin/env python
import time
import pigpio
PIN=4
TOGGLE=10000
pi = pigpio.pi() # Connect to local Pi.
s = time.time()
for i in range(TOGGLE):
pi.write(PIN, 1)
pi.write(PIN, 0)
e = time.time()
print("pigpio did {} toggles per second".format(int(TOGGLE/(e-s))))
pi.stop()
Timing that shows a speed improvement to roughly 800 toggles per second.
Now let's use a script.
pigs proc tag 999 w 22 1 w 22 0 dcr p0 jp 999
Ignore the details for now.
Let's time the script running.
Again, ignore the details for now.
time (pigs procr 0 10000000; while a=$(pigs procp 0); [[ ${a::1} -eq 2 ]];.br
do sleep 0.2; done)
The script takes roughly 12 seconds to complete, or 800,000 toggles per second.
That is the advantage of a stored script.
Some details.
pigs proc tag 999 w 22 1 w 22 0 dcr p0 jp 999
proc introduces a script. Everything after proc is part of the
script.
tag 999 names the current position in the script.
w 22 1 writes 1 to GPIO 22.
w 22 0 writes 0 to GPIO 22.
dcr p0 decrements parameter 0.
jp 999 jumps to tag 999 if the result is positive.
time (pigs procr 0 10000000; while a=$(pigs procp 0); [[ ${a::1} -eq 2 ]];.br
do sleep 0.2; done)
pigs procr 0 10000000 starts script 0 with parameter 0 of 10 million.
The rest is bash apart from
pigs procp 0 asks for the status and parameters of script 0. The status will be 2 while the script is running and 1 when it is complete.
A script runs within a virtual machine with
a 32 bit accumulator A.
a flags register F.
a program counter PC.
Each script has
10 parameters named 0 through 9.
150 variables named 0 through 149.
50 labels which are named by any unique number.
Many pigpio commands may be used within a script. However some commands do not work within the script model as designed and are not permitted.
The following commands are not permitted within a script:
File - FL FO FR FW
I2C - BI2CZ I2CPK I2CRD I2CRI I2CRK I2CWD I2CWI I2CWK I2CZ
Misc - BSCX CF1 CF2 SHELL
Script control - PARSE PROC PROCD PROCP PROCR PROCS PROCU
Serial - SERO SERR SERW SLR
SPI - BSPIO BSPIX SPIR SPIW SPIX
Waves - WVAG WVAS WVCHA WVGO WVGOR
The following commands are only permitted within a script:
Command Description Definition ADD x Add x to accumulator A+=x; F=A AND x And x with accumulator A&=x; F=A CALL L Call subroutine at tag L push(PC+1); PC=L CMP x Compare x with accumulator F=A-x DCR y Decrement register --*y; F=*y DCRA Decrement accumulator --A; F=A DIV x Divide x into accumulator A/=x; F=A EVTWT Wait for an event to occur A=wait(x); F=A HALT Halt Halt INR y Increment register ++*y; F=*y INRA Increment accumulator ++A; F=A JM L Jump if minus to tag L if (F<0) PC=L JMP L Jump to tag L PC=L JNZ L Jump if non-zero to tag L if (F) PC=L JP L Jump if positive to tag L if (F>=0) PC=L JZ L Jump if zero to tag L if (!F) PC=L LD y x Load register with x *y=x LDA x Load accumulator with x A=x MLT x Multiply x with accumulator A*=x; F=A MOD x Modulus x with accumulator A%=x; F=A OR x Or x with accumulator A|=x; F=A POP y Pop register y=pop() POPA Pop accumulator A=pop() PUSH y Push register push(y) PUSHA Push accumulator push(A) RET Return from subroutine PC=pop() RL y x Rotate left register x bits *y<<=x; F=*y RLA x Rotate left accumulator x bits A<<=x; F=A RR y x Rotate right register x bits *y>>=x; F=*y RRA x Rotate right accumulator x bits A>>=x; F=A STA y Store accumulator in register y=A SUB x Subtract x from accumulator A-=x; F=A SYS str Run external script (/opt/pigpio/cgi/str) system(str); F=A TAG L Label the current script position N/A WAIT x Wait for a GPIO in x to change state A=wait(x); F=A X y1 y2 Exchange contents of registers y1 and y2 t=*y1;*y1=*y2;*y2=t XA y Exchange contents of accumulator and register t=A;A=*y;*y=t XOR x Xor x with accumulator A^=x; F=A
x may be a constant, a parameter (p0-p9), or a variable (v0-v149).
y may be a parameter (p0-p9), or a variable (v0-v149). If p or v isn't specified y is assumed to be a variable.
The EVTWT command parameter is a bit-mask with 1 set for events of interest.
The WAIT command parameter is a bit-mask with 1 set for GPIO of interest.
The SYS script receives two unsigned parameters: the accumulator A and the current GPIO levels.
pigpiod(1), pig2vcd(1), pigpio(3), pigpiod_if(3), pigpiod_if2(3)
joan@abyz.me.uk
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