phycat 0.0.8

Phycat Tools and CLI

This repo contains the phycat python package which contains the CLI utility and the library for using phycat in other tools.

Phycat is a tool for remotely configuring and using hardware peripherals. The typical use case is to run a ‘server’ on an embedded device and a client can connect to use the peripheral interfaces (e.g. GPIO, I2C, SPI, etc). Linux machines can also run with a configuration file to define the interfaces it exposes.

Using CLi

Starting the CLI

phycat -c tcp:localhost:2020                # Connect to a phycat over tcp at port 2020

phycat -c serial:/dev/ttyUSB0               #connect to a phycat server device over serial
phycat -c serial:/dev/ttyUSB0:115200-8E2    #connect to a phycat server device over serial with specific serial settings

phycat -c tcp:8020 -s my-config.yml            #start a phycat server in linux using my-config.yml to define interfaces

Using the CLI

After connecting to a phycat server, you get a CLI with some information and auto completion for the device

Set up an i2c device and write to it

$> ls  # list all interfaces and devices

  ...
  i2c0:
    capabilities:
      supports_master: true
      supports_slave: true
      speeds: [ 100000, 400000, 1000000]
      max_7bit_addresses: 4
      max_10bit_addresses: 2

  ...

$> config i2c0 --role master --speed 1000000 --cache-memory # set up the i2c interface to be a master at 1Mhz and cache memory as it reads and writes

$> i2c0.scan # scan for i2c devices on the bus

          0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
      00: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
      10: -- -- -- -- -- -- -- -- -- -- -- -- WR -- -- --
      20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
      30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
      40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
      50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
      60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
      70: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --


$> i2c0.write --dev 0x1c 0x02 0x01 0x02 # raw write of 3 bytes to an i2c device at address 0x1c
$> i2c0.write --dev 0x1c --reg 0x02 0x01 0x02 0x03 0x04 #If a reg is specified, it wll write to that register on the device
$> i2c0.read --dev 0x1c --reg 0x30 2 # read 3 bytes from an i2c device at address 0x1c starting at register 0x10

  <<<[i2c0] address: 0x1c , data: [ 0x17 , 0x38 ]

$> ls i2c0 # show details for the i2c0 interface

  ...
  i2c0:
    capabilities:
      supports_master: true
      supports_slave: true
      speeds: [ 100000, 400000, 1000000 ]
      max_7bit_addresses: 4
      max_10bit_addresses: 2
      pins:
        - {sda: A3, scl: A2}  # when sda and scl are not specified, the first available pins are used
        - {sda: A4, scl: A5}
        - {sda: A6, scl: A7}
    config:
      role: master
      speed: 1000000
      sda: A3
      scl: A2
    devices:
      '0x1c':
        address: 0x1c
        memory:
           0x00: -- -- 01 02 03 04 -- -- -- -- -- -- -- -- -- -- | .....  # memory cache of the device,
           ...                                                            # broken into contiguos blocks
           0x30: 17 38 -- -- -- -- -- -- -- -- -- -- -- -- -- -- | .8...

Pwm example

$> ls

  ...
  gpio0:
    capabilities:
      supports_input: true
      supports_output: true
      supports_interrupts: true
      supports_pwm_output: true
      supports_pwm_input: true
      supports_dshot_output: true
      supports_dshot_input: true
  gpio1:
    capabilities:
      supports_input: true
      supports_output: true
      supports_interrupts: true
      supports_pwm_output: true
      supports_pwm_input: true
      supports_dshot_output: true
      supports_dshot_input: true

$> config gpio0 --mode pwm_output
$> config gpio1 --mode pwm_input  --jitter_filter_us 10 # set up the gpio1 interface to be a pwm input with a jitter of 10us
$> gpio0.pwm --period 2000 --pulse 1000 # set the pwm period to 2ms and the pulse width to 1ms

  <<<[gpio1] period: 2000, pulse: 1000 #If the pins are connected, you should get a message that the pwm value has changed

Data formats

The CLI accepts data in a few formats.

$> uart0.write 0x01 0x02 0x03 0x04 0x05 0x06 0x07 0x08 0x09 0x0A # raw hex bytes
$> uarto.write $(b'hello world') # use $() to evaluate python code. must return bytes or bytearray
$> uart0.write SGVsbG8gV29ybGQ= # base64 encoded data

Example Config File

Below is an example server side configuration file exposing a uart, i2c, spi and can interface. This configuration also includes a local phycat device. When it runs, the server will connect to that device and expose all of its interfaces along with its own.

interfaces:
  - name: uart-0
    type: uart
    driver: linux-serial    # use the default linux-serial driver
    driver_options:
        device: /dev/ttyUSB0
    bauds: [ 9600, 115200, 230400, 460800, 921600]

  - name: i2c-0
    type: i2c
    driver: pigpio-i2c      # Use the pigpio i2c driver for this interface
    driver_options:
        sda: 1                  # Use GPIO 1 for SDA ()
        scl: 0
    supports_master: true
    supports_slave: false

  - name: spi-0
    type: spi
    driver: linux-spi
    driver_options:
        device: /dev/spidev0.0
    supports_master: true
    supports_slave: false
    max_speed: 1000000

  - name: can-0
    type: can
    driver: linux-slcand
    devive: /dev/ttyACM0
    supports_fd: true
    supports_extended: true

  - name: phycat-serial
    type: phycat
    driver: phycat
    connection: serial:/dev/ttyS3:115200-8E2