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Hardware tools provide low-level bus communication for embedded Linux systems like Raspberry Pi, BeagleBone, and industrial IoT devices.
Hardware tools are Linux-only and require appropriate kernel drivers and permissions.

​
i2c

Interact with I2C bus devices for reading sensors and controlling peripherals.

​
Input Parameters

​
action
string
required
Action to perform:
  • detect - List available I2C buses
  • scan - Find devices on a bus
  • read - Read bytes from device
  • write - Send bytes to device
​
bus
string
I2C bus number (e.g., “1” for /dev/i2c-1). Required for scan/read/write.
​
address
integer
7-bit I2C device address (0x03-0x77). Required for read/write.
​
register
integer
Register address to read from or write to. If set, sends register byte before read/write.
​
data
array
Bytes to write (0-255 each). Required for write action.
​
length
integer
default:"1"
Number of bytes to read (1-256). Used with read action.
​
confirm
boolean
Must be true for write operations. Safety guard to prevent accidental writes.

​
Actions

​
detect

List available I2C buses by scanning /dev/i2c-* devices. Example: 
{
  "action": "detect"
}
Response: 
[
  {"path": "/dev/i2c-0", "bus": "0"},
  {"path": "/dev/i2c-1", "bus": "1"}
]

​
scan

Scan an I2C bus for connected devices (addresses 0x03-0x77). Example: 
{
  "action": "scan",
  "bus": "1"
}
Response: 
{
  "bus": "1",
  "devices": [
    {"address": "0x38", "description": "Possible sensor/peripheral"},
    {"address": "0x68", "description": "Possible sensor/peripheral"}
  ]
}

​
read

Read bytes from an I2C device. Read from device (no register): 
{
  "action": "read",
  "bus": "1",
  "address": 56,
  "length": 4
}
Read from specific register: 
{
  "action": "read",
  "bus": "1",
  "address": 56,
  "register": 0,
  "length": 6
}
Response: 
{
  "bus": "1",
  "address": "0x38",
  "register": "0x00",
  "data": [28, 123, 45, 67, 89, 12],
  "hex": "1c 7b 2d 43 59 0c"
}

​
write

Write bytes to an I2C device. Requires confirm: true for safety. Write to device: 
{
  "action": "write",
  "bus": "1",
  "address": 56,
  "data": [0x03, 0x01],
  "confirm": true
}
Write to specific register: 
{
  "action": "write",
  "bus": "1",
  "address": 56,
  "register": 0,
  "data": [0xFF],
  "confirm": true
}

​
Error Conditions

  • I2C is only supported on Linux - Non-Linux OS detected
  • action is required - Missing action parameter
  • unknown action: {action} - Invalid action value
  • bus is required - Missing bus for scan/read/write
  • invalid bus identifier - Bus must be numeric (e.g., “1”)
  • address is required - Missing address for read/write
  • address must be in valid 7-bit range (0x03-0x77) - Invalid address
  • data is required for write - Missing data array
  • confirm must be true for write operations - Safety confirmation missing

​
Platform Requirements

Kernel modules: 
sudo modprobe i2c-dev
Permissions: 
sudo usermod -aG i2c $USER
# or
sudo chmod 666 /dev/i2c-*
Device tree (Raspberry Pi): 
# Enable I2C in /boot/config.txt
dtparam=i2c_arm=on

​
spi

Interact with SPI bus devices for high-speed peripheral communication.

​
Input Parameters

​
action
string
required
Action to perform:
  • list - Find available SPI devices
  • transfer - Full-duplex send/receive
  • read - Receive bytes (sends zeros)
​
device
string
SPI device identifier (e.g., “2.0” for /dev/spidev2.0). Required for transfer/read.
​
speed
integer
default:"1000000"
SPI clock speed in Hz (1 Hz - 125 MHz). Default: 1 MHz.
​
mode
integer
default:"0"
SPI mode (0-3). Sets CPOL and CPHA:
  • Mode 0: CPOL=0, CPHA=0
  • Mode 1: CPOL=0, CPHA=1
  • Mode 2: CPOL=1, CPHA=0
  • Mode 3: CPOL=1, CPHA=1
​
bits
integer
default:"8"
Bits per word (1-32). Default: 8.
​
data
array
Bytes to send (0-255 each). Required for transfer action.
​
length
integer
Number of bytes to read (1-4096). Required for read action.
​
confirm
boolean
Must be true for transfer operations. Safety guard to prevent accidental writes.

​
Actions

​
list

Find available SPI devices by scanning /dev/spidev*. Example: 
{
  "action": "list"
}
Response: 
[
  {"path": "/dev/spidev0.0", "device": "0.0"},
  {"path": "/dev/spidev2.0", "device": "2.0"}
]

​
transfer

Full-duplex SPI transfer (simultaneous send and receive). Example: 
{
  "action": "transfer",
  "device": "2.0",
  "speed": 1000000,
  "mode": 0,
  "bits": 8,
  "data": [0x9F, 0x00, 0x00],
  "confirm": true
}
Response: 
{
  "device": "2.0",
  "speed": 1000000,
  "mode": 0,
  "bits": 8,
  "sent": [159, 0, 0],
  "received": [239, 64, 24],
  "hex": "ef 40 18"
}

​
read

Read bytes from SPI device (sends zeros during read). Example: 
{
  "action": "read",
  "device": "2.0",
  "length": 8,
  "speed": 500000
}
Response: 
{
  "device": "2.0",
  "length": 8,
  "data": [0, 12, 34, 56, 78, 90, 123, 255],
  "hex": "00 0c 22 38 4e 5a 7b ff"
}

​
Error Conditions

  • SPI is only supported on Linux - Non-Linux OS detected
  • action is required - Missing action parameter
  • unknown action: {action} - Invalid action value
  • device is required - Missing device for transfer/read
  • invalid device identifier: must be in format "X.Y" - Invalid device format
  • speed must be between 1 Hz and 125 MHz - Invalid speed
  • mode must be 0-3 - Invalid mode
  • bits must be between 1 and 32 - Invalid bits per word
  • data is required for transfer - Missing data array
  • length is required for read - Missing length parameter
  • confirm must be true for transfer operations - Safety confirmation missing

​
Platform Requirements

Kernel modules: 
sudo modprobe spidev
Permissions: 
sudo usermod -aG spi $USER
# or
sudo chmod 666 /dev/spidev*
Device tree (Raspberry Pi): 
# Enable SPI in /boot/config.txt
dtparam=spi=on

​
SPI Mode Reference

ModeCPOLCPHAClock PolarityClock Phase
000Idle lowSample on leading edge
101Idle lowSample on trailing edge
210Idle highSample on leading edge
311Idle highSample on trailing edge

​
Common Use Cases

Flash memory (W25Q series): 
{
  "action": "transfer",
  "device": "0.0",
  "speed": 10000000,
  "mode": 0,
  "data": [0x9F, 0x00, 0x00, 0x00],
  "confirm": true
}
ADC (MCP3008): 
{
  "action": "transfer",
  "device": "0.0",
  "speed": 1000000,
  "mode": 0,
  "data": [0x01, 0x80, 0x00],
  "confirm": true
}

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