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The rgs shell utility

Introduction

rgs is a program which allows remote control of the GPIO and other functions of Linux SBCs running the rgpiod daemon.

The rgpiod daemon must be running on the SBCs you wish to control.

Features

reading and writing GPIO singly and in groups
software timed PWM and waves
GPIO callbacks
pipe notification of GPIO events
I2C wrapper
SPI wrapper
serial link wrapper
simple file handling
creating and running scripts on the rgpiod daemon

Usage

rgs {command}+

rgs will show the result of the command on screen.

The rgs process returns an exit status (which can be displayed with the command echo $?).

RGS_OK            0
RGS_CONNECT_ERR 255
RGS_OPTION_ERR  254
RGS_SCRIPT_ERR  253

If an error was detected a message will have been written to stderr. This is likely to be more informative than the message returned by rgs.

Several commands may be entered on a line. If present PROC and PARSE must be the last command on a line.

Notes

rgs does not show the status of successful commands unless the command itself returns data. The status (0) will be returned to rgs but will be discarded.

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 rgs -a option can be used to force the display as ASCII and the rgs -x option can be used to force the display as hex.

E.g. assuming the transmitted serial data is the letters ABCDEONM

$ rgs serr 4 100 # assumes serial data available from handle 4
8 65 66 67 68 69 79 78 77

$ rgs -a serr 4 100
8 ABCDEONM

$ rgs -x serr 4 100
8 41 42 43 44 45 4f 4e 4d

Permissions

Generally objects created on the rgpiod daemon exist for the duration of the socket connection.

For a Python script this will be for the duration of the script. For a program linked with rgpio this will be for the duration of the program.

For rgs it is the command line.

This means that the following command will achieve little

rgs go 0 # get handle to gpiochip 0

The daemon will delete the handle as soon as the rgs command has finished.

To preserve the handle it must be shared.

A lot of the examples will show the command c 1 (use share id 1). This means the handle is preserved and may be used in subsequent commands.

rgs c 1 go 0 # get and preserve handle to gpiochip 0

If the LG_SHARE environment variable exists that share will be automatically used in rgs commands.

E.g. export LG_SHARE=12 will automatically use share id 12.

If a command is privileged it is indicated in the notes for the command. The examples given here assume the daemon access control system is not active (so any user can use privileged commands).

If the LG_USER environment variable exists that user will be automatically used in rgs commands. This only has an effect if the rgpiod daemon is running with access control enabled.

E.g. export LG_USER=joan will automatically use user joan.

Overview


FILES

FO file mode	File open
FC h	File close

FR h num	File read
FW h bvs	File write

FS h num from	File seek

FL pat num	File list

GPIO

GO gc	gpiochip open device
GC h	gpiochip close device

GIC h	gpiochip information
GIL h g	gpiochip line information

GMODE h g	GPIO get mode

GSI h g	GPIO claim for input (simple)
GSIX h lf g	GPIO claim for input

GSO h g	GPIO claim for output (simple)
GSOX h lf g v	GPIO claim for output

GSA h g nfyh	GPIO claim for alerts (simple)
GSAX h lf ef g nfyh	GPIO claim for alerts

GSF h g	GPIO free

GSGI h g*	GPIO group claim for inputs (simple)
GSGIX h lf g*	GPIO group claim for inputs

GSGO h g*	GPIO group claim for outputs (simple)
GSGOX h lf g* v*	GPIO group claim for outputs

GSGF h g	GPIO group free

GR h g	GPIO read
GW h g v	GPIO write

GGR h g	GPIO group read

GGW h g gbits	GPIO group write (simple)
GGWX h g gbits gmask	GPIO group write

GP h g mon moff	GPIO tx pulse (simple)
GPX h g mon moff off cyc	GPIO tx pulse

P h g pf pdc	GPIO tx PWM (simple)
PX h g pf pdc off cyc	GPIO tx PWM

S h g spw	GPIO tx servo pulses (simple)
SX h g spw sf off cyc	GPIO tx servo pulses

GWAVE h g p*	GPIO group tx wave
GBUSY h g k	GPIO or group tx busy
GROOM h g k	GPIO or group tx entries

GDEB h g us	GPIO debounce time
GWDOG h g us	GPIO watchdog time

I2C

I2CO ib id if	I2C open device
I2CC h	I2C close device

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	I2C zip

NOTIFICATIONS

NO	Notification open
NC h	Notification close
NP h	Notification pause
NR h	Notification resume

SCRIPTS

PROC t	Script store
PROCR h pars	Script run
PROCU h pars	Script update parameters
PROCP h	Script get status and parameters
PROCS h	Script stop
PROCD h	Script delete

PARSE t	Script validate

SERIAL

SERO dev b sef	Serial open device
SERC h	Serial close device

SERRB	Serial read byte
SERWB h bv	Serial write byte

SERR h num	Serial read bytes
SERW h bvs	Serial write bytes

SERDA h	Serial data available

SHELL

SHELL name str	Execute a shell command

SPI

SPIO spd spc b spf	SPI open device
SPIC h	SPI close device

SPIR h num	SPI read bytes
SPIW h bvs	SPI write bytes

SPIX h bvs	SPI transfer bytes

UTILITIES

LGV	Get lg library version
SBC	Get SBC's host name

CGI cid	Get internal configuration setting
CSI cid v	Set internal configuration setting

T/TICK	Get nanoseconds since the epoch

MICS v	Microseconds delay
MILS v	Milliseconds delay

U/USER	Set user

C/SHARE	Set share

LCFG	Reload permits configuration file
PCD	Print daemon configuration directory
PWD	Print daemon working directory

Commands

FILES

FO file mode - File open

This is a privileged command. See permits.

This function returns a handle to a file opened in a specified mode.

Upon success a handle (>=0) is returned. On error a negative status code will be returned.

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 the user that launched the daemon with permissions owner read and write.

Example

ls /ram/*.c
/ram/q.c     /ram/qdhtxx.c  /ram/q-errcod.c  /ram/q_t1.c
/ram/q-c1.c  /ram/Q-err.c   /ram/q-group.c   /ram/q_t2.c

$ rgs c 1 fo /ram/q.c 1  # read access
1

$ rgs c 1 fo /ram/new.c 1 # file does not exist
-58
ERROR: file open failed

$rgs c 1 fo /ram/new.c 9 # can not create file
-67
ERROR: no permission to access file

FC h - File close

This command closes a file previously opened by FO.

Upon success nothing is returned. On error a negative status code will be returned.

Example

$ rgs c 1 fc 1 # First close okay.

$ rgs c 1 fc 1 # Second fails.
-5
ERROR: unknown handle

FR h num - File read

This command returns up to num bytes of data read from the file.

Upon success the count of returned bytes followed by the bytes themselves is returned. On error a negative status code will be returned.

Example

$ rgs c 1 fr 0 10
5 48 49 128 144 255

$ rgs c 1 fr 0 10
0

FW h bvs - File write

This command writes bvs bytes to the file.

Upon success nothing is returned. On error a negative status code will be returned.

Example

$ rgs c 1 fw 0 23 45 67 89

FS h num from - File seek

This command seeks to a position within the file.

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

$ rgs c 1 fs 0 200 0 # Seek to start of file plus 200
200

$ rgs c 1 fs 0 0 1 # Return current position
200

$ rgs c 1 fs 0 0 2 # Seek to end of file, return size
296235

FL pat num - File list

This command returns a list of the files matching pat. Up to num bytes may be returned.

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.

This is a privileged command. See permits.

Example

$ rgs -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

$ rgs -a fl "/sys/bus/*" 5000
ERROR: no permission to access file
-67

GPIO

GO gc - gpiochip open device

This is a privileged command. See permits.

This command opens a gpiochip.

Example

$ rgs c 1 go 0 # open /dev/gpiochip0
1
$ rgs c 1 go 23 # try to open /dev/gpiochip23
-78
ERROR: can not open gpiochip

GC h - gpiochip close device

This command closes a gpiochip previously opened by GO.

Example

$ rgs c 1 gc 1 # first close ok
$ rgs c 1 gc 1 # already closed
-5
ERROR: unknown handle

GIC h - gpiochip information

This command gets information for an opened gpiochip. In particular it gets the number of GPIO on the gpiochip, its name, and its usage.

Example

$ rgs c 1 gic 1
54 "gpiochip0" "pinctrl-bcm2835"

GIL h g - gpiochip line information

This command gets information for GPIO g of an opened gpiochip. In particular it gets the GPIO number, kernel usage flags, its user, and its purpose.

The usage flags are bits.

Bit value	Bit meaning
1	GPIO in use by the kernel
2	GPIO is an output
4	GPIO is active low
8	GPIO is open drain
16	GPIO is open source

The user and purpose fields are filled in by the software which has claimed the GPIO and may be blank.

Example

$ for ((i=2; i<10; i++)); do rgs c 1 gil 1 $i; done
2 0 "" ""
3 0 "" ""
4 11 "" "onewire.0"
5 0 "" ""
6 0 "" ""
7 7 "" "spi0 CS1"
8 7 "" "spi0 CS0"
9 0 "" ""

GMODE h g - GPIO get mode

This command gets the mode for GPIO g of an opened gpiochip.

Mode bit	Value	Meaning
0	1	Kernel: In use by the kernel
1	2	Kernel: Output
2	4	Kernel: Active low
3	8	Kernel: Open drain
4	16	Kernel: Open source
5	32	Kernel: ---
6	64	Kernel: ---
7	128	Kernel: ---
8	256	LG: Input
9	512	LG: Output
10	1024	LG: Alert
11	2048	LG: Group
12	4096	LG: ---
13	8192	LG: ---
14	16384	LG: ---
15	32768	LG: ---

GSI h g - GPIO claim for input (simple)

This command claims GPIO g for input.

Example

$ rgs c 1 gsi 1 23 # claim GPIO 23 for input.

GSIX h lf g - GPIO claim for input

This command claims GPIO g for input.

The line flags lf may be used to set the GPIO as active low, open drain, or open source.

Example

$ rgs c 1 gsi 1 0 23 # claim GPIO 23 for input.

GSO h g - GPIO claim for output (simple)

This command claims GPIO g for output.

The GPIO will be initialised low.

Example

$ rgs c 1 gso 1 25 # claim GPIO 25 for low output.

GSOX h lf g v - GPIO claim for output

This command claims GPIO g for output.

The line flags lf may be used to set the GPIO as active low, open drain, or open source.

If v is zero the GPIO will be initialised low. If any other value is used the GPIO will be initialised high.

Example

$ rgs c 1 gso 1 0 25 # claim GPIO 25 for high output.

GSA h g nfyh - GPIO claim for alerts (simple)

This command claims GPIO g for alerts.

Alerts will be generated for both edges.

The alerts will be sent to a previously opened notification pipe nfyh.

GSAX h lf ef g nfyh - GPIO claim for alerts

This command claims GPIO g for alerts.

The line flags lf may be used to set the GPIO as active low, open drain, or open source.

The event flags ef specify whether alerts should be generated on a rising edge, falling edge, or both edges.

The alerts will be sent to a previously opened notification pipe nfyh.

GSF h g - GPIO free

This command releases GPIO g. The GPIO may now be claimed by another user or for a different purpose.

GSGI h g* - GPIO group claim for inputs (simple)

This command claims a group of GPIO for inputs.

g* is a list of one or more GPIO. The first GPIO in the list is called the group leader and is used to reference the group as a whole.

Example

$ rgs c 1 gsgi 1 16 17 18 19 20 21

GSGIX h lf g* - GPIO group claim for inputs

This command claims a group of GPIO for inputs. All the GPIO share the same line flag setting.

The line flags lf may be used to set the GPIO as active low, open drain, or open source.

g* is a list of one or more GPIO. The first GPIO in the list is called the group leader and is used to reference the group as a whole.

Example

$ rgs c 1 gsgix 1 0 16 17 18 19 20 21

GSGO h g* - GPIO group claim for outputs (simple)

This command claims a group of GPIO for outputs.

g* is a list of one or more GPIO. The first GPIO in the list is called the group leader and is used to reference the group as a whole.

The GPIO will be initialised low.

Example

$ rgs c 1 gsgo 1 22 23 24 25

GSGOX h lf g* v* - GPIO group claim for outputs

This command claims a group of GPIO for outputs. All the GPIO and share the same line flag setting.

The line flags lf may be used to set the GPIO as active low, open drain, or open source.

g* is a list of one or more GPIO. The first GPIO in the list is called the group leader and is used to reference the group as a whole.

v* is a list of initialisation values for the GPIO. If a value is zero the corresponding GPIO will be initialised low. If any other value is used the corresponding GPIO will be initialised high.

Example

$ rgs c 1 gsgox 1 0 22 23 24 25 1 1 1 1

GSGF h g - GPIO group free

This command releases the group of GPIO identified by the group leader g. The GPIO may now be claimed by another user or for a different purpose.

Example

rgs c 1 gsgf 1 22

GR h g - GPIO read

This command returns the current value (0 or 1) of GPIO g.

This command will work for any claimed GPIO (even if a member of a group). For an output GPIO the value returned will be that last written to the GPIO.

Example

$ rgs c 1 gr 1 22
1

GW h g v - GPIO write

This command sets the value (0 or 1) of GPIO g.

This command will work for any GPIO claimed as an output (even if a member of a group).

If v is zero the GPIO will be set low. If any other value is used the GPIO will be set high.

GGR h g - GPIO group read

This command reads a group of GPIO identified by group leader g.

This command will work for an output group as well as an input group. For an output group the value returned will be that last written to the group GPIO. Note that this command will also work on an individual GPIO claimed as an input or output as that is treated as a group with one member.

Two values are returned. The first is the group size (the number of GPIO in the group). The second is the group bits as a decimal value.

Bit 0 is the level of the group leader.
Bit 1 is the level of the second GPIO in the group.
Bit g is the level of GPIO g+1 in the group.

Example

$ rgs c 1 gsgi 1 0 16 17 18 19 20 21
$ rgs c 1 ggr 1 16
6 49 # six GPIO, group leader (16) high, 17-19 low, 20-21 high

GGW h g gbits - GPIO group write (simple)

This command writes a group of GPIO identified by group leader g.

The values of each GPIO of the group are set according to the bits
of gbits.

Bit 0 sets the level of the group leader.
Bit 1 sets the level of the second GPIO in the group.
Bit g sets the level of GPIO g+1 in the group.

Example

$ rgs c 1 ggr 1 22
4 15
$ rgs c 1 ggw 1 22 5
$ rgs c 1 ggr 1 22
4 5
$ rgs c 1 ggw 1 22 10
$ rgs c 1 ggr 1 22
4 10

GGWX h g gbits gmask - GPIO group write

$ rgs c 1 ggr 1 22
4 15
$ rgs c 1 ggw 1 22 5 15
$ rgs c 1 ggr 1 22
4 5
$ rgs c 1 ggw 1 22 10 0
$ rgs c 1 ggr 1 22
4 5
$ rgs c 1 ggw 1 22 10 15
$ rgs c 1 ggr 1 22
4 10

GP h g mon moff - GPIO tx pulse (simple)

This command starts software timed pulses on GPIO g .

Each cycle consists of mon microseconds of GPIO high followed by moff microseconds of GPIO low.

PWM is characterised by two values, its frequency (number of cycles per second) and its duty cycle (percentage of high time per cycle).

The set frequency will be 1000000 / (mon + moff) Hz.

The set duty cycle will be mon / (mon + moff) * 100 %.

E.g. if mon is 50 and moff is 100 the frequency will be 6666.67 Hz and the duty cycle will be 33.33 %.

GPX h g mon moff off cyc - GPIO tx pulse

This command starts software timed pulses on GPIO g .

cyc cycles are transmitted (0 means infinite). Each cycle consists of mon microseconds of GPIO high followed by moff microseconds of GPIO low.

PWM is characterised by two values, its frequency (number of cycles per second) and its duty cycle (percentage of high time per cycle).

The set frequency will be 1000000 / (mon + moff) Hz.

The set duty cycle will be mon / (mon + moff) * 100 %.

E.g. if mon is 50 and moff is 100 the frequency will be 6666.67 Hz and the duty cycle will be 33.33 %.

off is a microsecond offset from the natural start of the PWM cycle.

For instance if the PWM frequency is 10 Hz the natural start of each cycle is at seconds 0, then 0.1, 0.2, 0.3 etc. In this case if the offset is 20000 microseconds the cycle will start at seconds 0.02, 0.12, 0.22, 0.32 etc.

Another command may be issued to the GPIO before the last has finished.

If the last command had infinite cycles (cyc of 0) then it will be replaced by the new settings at the end of the current cycle. Otherwise it will be replaced by the new settings at the end of cyc cycles.

Multiple pulse settings may be queued in this way.

P h g pf pdc - GPIO tx PWM (simple)

This command starts software timed PWM on GPIO g .

PWM is characterised by two values, its frequency (number of cycles per second) and its duty cycle (percentage of high time per cycle).

PX h g pf pdc off cyc - GPIO tx PWM

This command starts software timed PWM on GPIO g .

PWM is characterised by two values, its frequency (number of cycles per second) and its duty cycle (percentage of high time per cycle).

off is a microsecond offset from the natural start of the PWM cycle.

For instance if the PWM frequency is 10 Hz the natural start of each cycle is at seconds 0, then 0.1, 0.2, 0.3 etc. In this case if the offset is 20000 microseconds the cycle will start at seconds 0.02, 0.12, 0.22, 0.32 etc.

Another PWM command may be issued to the GPIO before the last has finished.

If the last PWM had infinite cycles (cyc of 0) then it will be replaced by the new settings at the end of the current cycle. Otherwise it will be replaced by the new settings at the end of cyc cycles.

Multiple PWM settings may be queued in this way.

S h g spw - GPIO tx servo pulses (simple)

SX h g spw sf off cyc - GPIO tx servo pulses

This command starts software timed servo pulses on GPIO g .

I would only use software timed servo pulses for testing purposes. The timing jitter will cause the servo to fidget. This may cause it to overheat and wear out prematurely.

Another servo command may be issued to the GPIO before the last has finished.

If the last command had infinite cycles (cyc of 0) then it will be replaced by the new settings at the end of the current cycle. Otherwise it will be replaced by the new settings at the end of cyc cycles.

Multiple servo settings may be queued in this way.

GWAVE h g p* - GPIO group tx wave

This command starts a wave on GPIO group g .

p is a series of pulses to be transmitted on the GPIO group.

Each pulse is defined by the following triplet:

gbits the levels to set for the selected GPIO
gmask the GPIO to select
us the delay in microseconds before the next pulse

Another wave command may be issued to the GPIO group before the last has finished transmission.

Multiple waves may be queued in this way.

GBUSY h g k - GPIO or group tx busy

This command checks to see if a specified kind k of transmission is ongoing on a GPIO or GPIO group g .

The command returns 1 if transmission is ongoing, otherwise 0.

GROOM h g k - GPIO or group tx entries

This returns the number of slots there are to queue further transmissions of a specified kind k in the tx queue for GPIO or GPIO group g.

The command returns the number of free slots (0 for no free slots).

GDEB h g us - GPIO debounce time

This command sets the debounce time for GPIO g to us microseconds.

This command is only effective when the GPIO is being used as a source of alerts.

Any level changes shorter than the debounce setting will be discarded, i.e. they will not generate an alert.

Reported level changes will be timestamped us microseconds after the level change.

GWDOG h g us - GPIO watchdog time

This command sets the watchdog time for GPIO g to us microseconds.

This only affects alerts.

A watchdog alert will be sent if no edge alert has been issued for that GPIO in the previous watchdog microseconds.

Note that only one watchdog alert will be sent per stream of edge alerts. The watchdog is reset by the sending of a new edge alert.

The level is set to 2 for a watchdog alert.

I2C

I2CO ib id if - I2C open device

This is a privileged command. See permits.

This command returns a handle to access device id on I2C bus ib. The device is opened with flags if.

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

$ rgs c 1 i2co 1 0x70 0 # Bus 1, device 0x70, flags 0.
0

$ rgs c 1 i2co 1 0x53 0 # Bus 1, device 0x53, flags 0.
1

I2CC h - I2C close device

This command closes an I2C device previously opened by I2CO.

Upon success nothing is returned. On error a negative status code will be returned.

Example

$ rgs c 1 i2cc 0 # First close okay.

$ rgs c 1 i2cc 0 # Second fails.
-25
ERROR: unknown handle

I2CWQ h bit - SMB Write Quick: write bit

This command writes a single bit to the I2C device.

Upon success nothing is returned. On error a negative status code will be returned.

Example

$ rgs c 1 i2cwq 0 1

I2CRS h - SMB Read Byte: read byte

This command returns a single byte read from the I2C device.

Upon success a value between 0 and 255 will be returned. On error a negative status code will be returned.

Example

$ rgs c 1 i2crs 0
0

I2CWS h bv - SMB Write Byte: write byte

This command writes a single byte bv to the I2C device.

Upon success nothing is returned. On error a negative status code will be returned.

Example

$ rgs c 1 i2cws 0 0x12

$ rgs c 1 i2cws 0 0xff
-82
ERROR: I2C write failed

I2CRB h r - SMB Read Byte Data: read byte from register

This command returns a single byte read from register r of the I2C device.

Upon success a value between 0 and 255 will be returned. On error a negative status code will be returned.

Example

$ rgs c 1 i2crb 0 0
6

I2CWB h r bv - SMB Write Byte Data: write byte to register

This command writes a single byte bv to register r of the I2C device.

Upon success nothing is returned. On error a negative status code will be returned.

Example

$ rgs c 1 i2cwb 0 10 0x54

I2CRW h r - SMB Read Word Data: read word from register

This command returns a single 16 bit word read from register r of the I2C device.

Upon success a value between 0 and 65535 will be returned. On error a negative status code will be returned.

Example

$ rgs c 1 i2crw 0 0
6150

I2CWW h r wv - SMB Write Word Data: write word to register

This command writes a single 16 bit word wv to register r of the I2C device.

Upon success nothing is returned. On error a negative status code will be returned.

Example

$ rgs c 1 i2cww 0 0 0xffff

I2CRK h r - SMB Read Block Data: read data from register

This command returns between 1 and 32 bytes read from register r of the I2C device.

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

$ rgs c 1 i2crk 0 0
6 0 0 0 0 0 0

$ rgs c 1 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

I2CWK h r bvs - SMB Write Block Data: write data to register

This command writes between 1 and 32 bytes bvs to register r of the I2C device.

Upon success nothing is returned. On error a negative status code will be returned.

Example

rgs c 1 i2cwk 0 4 0x01 0x04 0xc0

I2CRI h r num - SMB Read I2C Block Data: read bytes from register

This command returns num bytes from register r of the I2C device.

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

$ rgs c 1 i2cri 0 0 16
16 237 155 155 155 155 155 155 155 155 155 155 155 155 155 155 155

I2CWI h r bvs - SMB Write I2C Block Data

This command writes between 1 and 32 bytes bvs to register r of the I2C device.

Upon success nothing is returned. On error a negative status code will be returned.

Example

$ rgs c 1 i2cwi 0 4 0x01 0x04 0xc0

I2CRD h num - I2C read device

This command returns num bytes read from the I2C device.

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. rgs imposes a limit of about 8000 bytes.

Example

$ rgs c 1 i2crd 0 16
16 6 24 0 0 0 0 0 0 0 0 0 0 0 0 32 78

I2CWD h bvs - I2C write device

This command writes a block of bytes bvs to the I2C device.

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. rgs imposes a limit of about 500 bytes.

This command operates on the raw I2C device.

Example

$ rgs c 1 i2cwd 0 0x01 0x02 0x03 0x04

I2CPC h r wv - SMB Process Call: exchange register with word

This command writes wv to register r of the I2C device and returns a 16-bit word read from the device.

Upon success a value between 0 and 65535 will be returned. On error a negative status code will be returned.

Example

$ rgs c 1 i2cpc 0 37 43210
39933

$ rgs c 1 i2cpc 0 256 43210
ERROR: bad i2c/spi/ser parameter
-81

I2CPK h r bvs - SMB Block Process Call: exchange data bytes with register

This command writes the data bytes bvs to register r of the I2C device 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

$ rgs c 1 i2cpk 0 0 0x11 0x12
6 0 0 0 0 0 0

I2CZ h bvs - I2C zip

This command executes a sequence of I2C operations. The operations to be performed are specified by the contents of bvs which contains the concatenated command codes and associated data.

The following command codes are supported:

Name	Cmd & Data	Meaning
End	0	No more commands
Escape	1	Next P is two bytes
Address	2 P	Set I2C address to P
Flags	3 lsb msb	Set I2C flags to lsb + (msb << 8)
Read	4 P	Read P bytes of data
Write	5 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

2 0x53  5 1 0x32  4 6
2 0x1E  5 1 0x03  4 6
2 0x68  5 1 0x1B  4 8
0

NOTIFICATIONS

NO - Notification open

This is a privileged command. See permits.

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.

The pipes are created in the daemon's working directory (the command pwd will show the working directory).

Notifications for handle x will be available at the pipe named .lgd-nfyx (where x is the handle number).

E.g. if the command returns 15 then the notifications must be read from .lgd-nfy15.

Example

$ rgs c 1 no
0

NC h - Notification close

This command closes a notification previously opened by NO.

Upon success nothing is returned. On error a negative status code will be returned.

Example

$ rgs c 1 nc 0 # First call succeeds.

$ rgs c 1 nc 1 # Second call fails.
-5
ERROR: unknown handle

NP h - Notification pause

This command pauses notifications.

Upon success nothing is returned. On error a negative status code will be returned.

Notifications for the handle are paused until a NR command.

Example

$ rgs c 1 np 0

NR h - Notification resume

This command resumes notifications.

Upon success nothing is returned. On error a negative status code will be returned.

Example

$ rgs c 1 nr 0

$ rgs c 1 nr 1
-5
ERROR: unknown handle

SCRIPTS

PROC t - Script store

This is a privileged command. See permits.

This command stores a script t for later execution.

If the script is valid a handle (>=0) is returned which is passed to the other script commands. On error a negative status code will be returned.

Example

$ rgs proc tag 123 w 4 0 mils 200 w 4 1 mils 300 dcr p0 jp 123
0

$ rgs proc tag 123 w 4 0 mils 5 w 4 1 mils 5 jmp 12
ERROR: script has unresolved tag
-63

PROCR h pars - Script run

This command runs stored script h passing it up to 10 optional parameters.

Upon success nothing is returned. On error a negative status code will be returned.

Example

$ rgs proc tag 123 w 4 0 mils 200 w 4 1 mils 300 dcr p0 jp 123
0

$ rgs procr 0 50 # Run script 0 with parameter 0 of 50.

$ rgs procp 0
2 44 0 0 0 0 0 0 0 0 0
$ rgs procp 0
2 37 0 0 0 0 0 0 0 0 0
$ rgs procp 0
2 10 0 0 0 0 0 0 0 0 0
$ rgs procp 0
2 5 0 0 0 0 0 0 0 0 0
$ rgs procp 0
2 2 0 0 0 0 0 0 0 0 0
$ rgs procp 0
1 -1 0 0 0 0 0 0 0 0 0

PROCU h pars - Script update parameters

This command sets the parameters of a stored script h passing it up to 10 parameters.

Upon success nothing is returned. On error a negative status code will be returned.

Example

$ rgs proc tag 0 hp 18 p0 p1 mils 1000 jmp 0
0
$ rgs procu 0 50 500000
$ rgs procr 0
$ rgs procu 0 100
$ rgs procu 0 200
$ rgs procu 0 200 100000

PROCP h - Script get status and parameters

This command returns the status of script h 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	ready
2	running
3	waiting
4	ended
5	halted
6	failed

Example

$ rgs procp 0
1 0 0 0 0 0 0 0 0 0 0

PROCS h - Script stop

This command stops a running script h.

Upon success nothing is returned. On error a negative status code will be returned.

Example

$ rgs procs 0

$ rgs procs 1
-5
ERROR: unknown handle

PROCD h - Script delete

This command deletes script h.

Upon success nothing is returned. On error a negative status code will be returned.

Example

$ rgs procd 1

$ rgs procd 1
ERROR: unknown handle
-5

PARSE t - Script validate

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.

This command may be used to find script syntax faults.

Example

$ rgs parse tag 100 w 22 1 mils 200 w 22 0 mils 800 jmp 100

$ rgs 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

SERIAL

SERO dev b sef - Serial open device

This is a privileged command. See permits.

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 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

$ rgs sero ttyAMA0 9600 0
0

$ rgs sero tty1 38400 0
1

SERC h - Serial close device

This command closes a serial device previously opened by SERO.

Upon success nothing is returned. On error a negative status code will be returned.

Example

$ rgs serc 0 # First close okay.

$ rgs serc 0 # Second close gives error.
-25
ERROR: unknown handle

SERRB - Serial read byte

This command returns a byte of data read from the serial device.

Upon success a number between 0 and 255 is returned. On error a negative status code will be returned.

Example

$ rgs serrb 0
23
$ rgs serrb 0
45

SERWB h bv - Serial write byte

This command writes a single byte bv to the serial device.

Upon success nothing is returned. On error a negative status code will be returned.

Example

$ rgs serwb 0 23
$ rgs serwb 0 0xf0

SERR h num - Serial read bytes

This command returns up to num bytes of data read from the serial 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

$ rgs serr 0 10
5 48 49 128 144 255

$ rgs serr 0 10
0

SERW h bvs - Serial write bytes

This command writes bytes bvs to the serial device.

Upon success nothing is returned. On error a negative status code will be returned.

Example

$ rgs serw 0 23 45 67 89

SERDA h - Serial data available

This command returns the number of bytes of data available to be read from the serial device.

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

$ rgs serda 0
0

SHELL

SHELL name str - Execute a shell command

This is a privileged command. See permits.

This command uses the system call to execute a shell script name with the given string str as its parameter.

Upon success the exit status of the system call is returned. On error a negative status code will be returned.

name must exist in a directory named cgi in the daemon's configuration directory 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
$ rgs shell scr1 hello world
256

# pass three parameters, hello, string with spaces, and world
$ rgs shell scr1 "hello 'string with spaces' world"
256

# pass one parameter, hello string with spaces world
$ rgs shell scr1 "\"hello string with spaces world\""
256

# non-existent script
$ rgs shell scr78 par1
32512

SPI

SPIO spd spc b spf - SPI open device

This is a privileged command. See permits.

Upon success a handle is returned. On error a negative status code will be returned.

Data will be transferred at b bits per second. The flags spf may be used to modify the default behaviour.

The flags consists of the least significant 2 bits.

1  0
m  m

mm defines the SPI mode.

Mode POL PHA
 0    0   0
 1    0   1
 2    1   0
 3    1   1

SPIC h - SPI close device

This command closes a SPI device previously opened by SPIO.

Upon success nothing is returned. On error a negative status code will be returned.

Example

$ rgs spic 1

$ rgs spic 1
-25
ERROR: unknown handle

SPIR h num - SPI read bytes

This command returns num bytes read from the SPI 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

$ rgs spir 0 10 # Read 10 bytes from the SPI device.
10 0 0 0 0 0 0 0 0 0 0

SPIW h bvs - SPI write bytes

This command writes bytes bvs to the SPI device.

Upon success nothing is returned. On error a negative status code will be returned.

Example

$ rgs spiw 0 0x22 0x33 0xcc 0xff

SPIX h bvs - SPI transfer bytes

This command writes bytes bvs to the SPI device.

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

$ rgs spix 0 0x22 0x33 0xcc 0xff
4 0 0 0 0

UTILITIES

LGV - Get lg library version

This command returns the lg library version.

Example

$ rgs lgv
lg_0.1.0.0

SBC - Get SBC's host name

This command returns the rgpiod daemon server name.

Example

$ rgs sbc
venus

CGI cid - Get internal configuration setting

This is a privileged command. See permits.

This command returns the value of an internal library configuration setting cid.

Example

$ rgs cgi 0
1

CSI cid v - Set internal configuration setting

This is a privileged command. See permits.

This command sets the value of the internal library configuration setting cid to v.

Example

$ rgs csi 0 3
$ rgs cgi 0
3

T/TICK - Get nanoseconds since the epoch

T and TICK are synonyms.

This command returns the number of nanoseconds since the epoch (start of 1970).

Example

$ rgs t
1601838936723095901
$ rgs tick
1601838940792322758

MICS v - Microseconds delay

This command delays execution for v microseconds.

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

$ rgs mics 20      # Delay 20 microseconds.
$ rgs mics 1000000 # Delay 1 second.
$ rgs mics 5100000 # Delay 5.1 seconds.
-24
ERROR: bad MICS delay (too large)

MILS v - Milliseconds delay

This command delays execution for v milliseconds.

Upon success nothing is returned. On error a negative status code will be returned.

Example

$ rgs mils   2000 # Delay 2 seconds.
$ rgs mils 301000 # Delay 301 seconds.
-25
ERROR: bad MILS delay (too large)

U/USER - Set user

U and USER are synonyms.

This command sets the current user and associated permissions.

Example

$ rgs u test1   # set user test1
$ rgs user test1 # set user test1
$ rgs u testx    # unknown user
-95
ERROR: bad secret for user

C/SHARE - Set share

C and SHARE are synonyms.

This command sets the share for handles.

The command has two uses. Firstly it sets the share id for any subsequently created handles on the current command line. Secondly it sets the share id to use to access any previously created handles on this or earlier command lines.

Example

rgs c 1       # use share id 1
rgs share 1   # use share id 1
rgs c 0       # switch off sharing
rgs share 867 # use share id 867

LCFG - Reload permits configuration file

This is a privileged command. See permits.

This command reloads the permits configuration file

Example

$ rgs lcfg
$ rgs lcfg
-93
ERROR: no permission to perform action
$ rgs lcfg
-93
ERROR: no permission to perform action

PCD - Print daemon configuration directory

This command prints the daemon configuration directory

Example

rgs pcd
/home/joan/LG/TEST

PWD - Print daemon working directory

This command prints the daemon working directory

Example

rgs pwd
/home/joan/LG

Parameters

b: baud

The command expects the baud rate in bits per second for the transmission of serial data (I2C/SPI/serial link, waves).

bit: bit value (0-1)

The command expects 0 or 1.

bv: a byte value (0-255)

The command expects a byte value.

bvs: byte values (0-255)

The command expects one or more byte values.

cid:

A number identifying an internal configuration item.

cid	meaning
0	debug level
1	minimum transmission period for PWM and waves

cyc: >= 0

The number of PWM pulses to generate. A value of 0 means infinite.

dev: a tty serial device

The command expects the name of a serial device without the leading /dev, e.g.

ttyAMA0
ttyUSB0
tty0
serial0

ef: GPIO event flags

The following values may be or'd to form the event flags.

Value	Meaning
1	Rising edge
2	Falling edge
3	Both edges

file: a file name

The file name must match an entry in the [files] section of the permits file.

from: 0-2

Position to seek from FS.

	From
0	start
1	current position
2	end

g: GPIO

The command expects a GPIO.

g*:

A list of one or more GPIO

gbits:

This value is used to set the levels of a GPIO group.

Bit 0 represents the level of the group leader.
Bit 1 represents the level of the second GPIO in the group.
Bit g represents the level of GPIO g+1 in the group.

gc: gpiochip (>=0)

The command expects a gpiochip number.

gmask:

This value is used to select GPIO from a GPIO group.

Bit 0 of the mask indicates item 1
Bit 1 of the mask indicates item 2
Bit g of the mask indicates item g+1

For example suppose the items are GPIO 5, 10, 23, 25, 11.

Bit 0 of the mask indicates GPIO 5
Bit 1 of the mask indicates GPIO 10
Bit 2 of the mask indicates GPIO 23
Bit 3 of the mask indicates GPIO 25
Bit 4 of the mask indicates GPIO 11

If a bit of the mask is high the corresponding GPIO will be selected.

E.g. in the above example if the mask has the value 17 GPIO 5 and GPIO 11 will be selected.

h: handle (>=0)

The command expects a handle.

A handle is a number referencing an object opened by one of FO, I2CO, NO, PROC, SERO, SPIO, GO.

ib: I2C bus (>=0)

The command expects an I2C bus number.

id: I2C device (0-0x7F)

The command expects the address of an I2C device.

if: I2C flags (0)

The command expects an I2C flags value. No flags are currently defined.

k:

A kind of transmission.

0 = PWM
1 = WAVE

lf: GPIO line flags

The following values may be or'd to form the line flags.

Value	Meaning
4	Active low
8	Open drain
16	Open source

mode: lgFile open mode

One of 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 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

moff: >= 0

The off period for a PWM pulse in microseconds.

mon: >= 0

The on period for a PWM pulse in microseconds.

name: the name of a script

Only alphanumeric characters, '-' and '_' are allowed in the name.

nfyh: >= 0

This associates a notification with a GPIO event.

num: maximum number of bytes to return (1-)

The command expects the maximum number of bytes to return.

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.

off: >= 0

The offset in microseconds from the nominal PWM pulse start.

p*:

One or more triplets of gbits, gmask, and us microsecond delay.

pars: script parameters

The command expects 0 to 10 numbers as parameters to be passed to the script.

pat: a file name pattern

A file path which may contain wildcards. To be accessible the path must match an entry in the [files] section of the permits file.

pdc: thousandths of %

PWM duty cycle between 0 % (0) and 100 % (100000).

pf: thousandths of Hz

PWM frequency between 0.1 Hz (100) and 10000 Hz (10000000). Use 0 for off.

r: register (0-255)

The command expects an I2C register number.

sef: serial flags (32 bits)

The command expects a flag value. No serial flags are currently defined.

sf: Hz (40-500)

Servo frequency

spc: SPI channel (>= 0)

The command expects a SPI channel.

spd: SPI device (>= 0)

The command expects a SPO device.

spf: SPI flags

See SPIO.

spw: 0=off, 500-2500 microseconds

Servo pulse width

str: a string

The command expects a string.

t: a string

The command expects a string.

us:

The command expects a time interval measured in microseconds.

v: value

The command expects a number.

v*:

A list of one or more values.

wv: word value (0-65535)

The command expects a word value.

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(2021-01-16 21:12)