arduino

Arduino controller code

Requirements

To be able to use the mega2560_256 board, you need to create a new board in your boards.txt (in the Arduino library base) which is a copy of mega2560 except the name (now mega2560_256, duh) and mega2560.build.core=arduino becomes mega2560_256.build.core=arduino_bigserial. Then you need to copy ..../hardware/arduino/cores/arduino/ to ..../hardware/arduino/cores/arduino_bigserial/ and in the new directory edit HardwareSerial.cpp to change #define SERIAL_BUFFER_SIZE 64 to #define SERIAL_BUFFER_SIZE 256.

Uploading the code to an Arduino

Run ./upload.sh <board> where board is any implemented board (such as "mega2560").

Running the emulator

The emulator requires shammam to be installed. To launch the emulator go to the emulation directory and run ./run_emulator.sh <board> where board is any implemented board (such as "mega2560").

PLEASE FIX ME: The script currently requires the shammam repository to be cloned in the same directory as this repository.

Communication Protocol

All communication happens by sending messages in the following format: [code (1 byte)][message length N (1 byte)][message (N bytes)]. Message codes are the following:

Messages Arduino sends

Code 0: Pin value update [0][3][pin_type][pin_index][reading]

• pin_type: 0 for digital pin, 1 for analog pin, 2 for virtual pin
• pin_index: Index of the pin
• reading: Current value at the pin

Messages accepted by Arduino

Code 1: Set pin mode (NON VIRTUAL PINS) [1][3][pin_type][pin_index][mode]

• pin_type: 0 for digital pin, 1 for analog pin, 2 for virtual pin
• pin_index: Index of the pin
• mode: If this pin is NOT virtual: 0 (input), 1 (output), 2 (PWM output), 3 (input with pullup resistor) or 4 (PWM output with smoothing)

Code 2: Set VIRTUAL pin mode [2][length][2][pin_index][virtual_pin_type][<pin-specific>]

• length: Length of the following bytes (pin-specific)
• pin_index: Index of the pin
• virtual_pin_type:
  • 0: Digital temperature sensor. pin-specific info: [temp_index]
    • temp_index: Index of the temperature sensor on the OneWire bus
  • 1: ISR Light controller (only makes a pulse during the AC wave). pin-specific info: [frequency][sync][pin]
    • frequency: frequency of the ISR light (50 or 60). All virtual pins of this type MUST have the same value for their frequency.
    • sync: the pin on which SYNC happens (zero-crossing is measured). All virtual pins of this type MUST have the same value for their sync.
    • pin: pin to output the waves for this light.
  • 2: Same as ISR light (1) but this doesn't make a pulse at the right time, but rather keeps the port HIGH until next zero cross
  • 3:
  • 4: NTC temperature sensor. pin-specific info: [analog_pin_index, k_resistance]
    • analog_pin_index: Index of the analog pin (i.e. 0, 1, 2, ...15 on the mega) to read the sensor
    • k_resistance: resistance value used (in thousands). pass 100 for 100kohm, 20 for 20kohm, etc...
  • 5: EmonLin current sensor: [analog_pin_index]
    • analog_pin_index: Index of the analog pin (i.e. 0 for A0, 1 for A1, 2, ...15 for A15 on the mega) to read the sensor

Code 3: Set pin output [3][3][pin_type][pin_index][output]

• pin_type: 0 for digital pin, 1 for analog pin, 2 for virtual pin
• pin_index: Index of the pin
• output: output value (0/1 for digital, or 0-255 for PWM)

Code 4: Read pin input [4][2][pin_type][pin_index]

The reading will be returned via a message (code 0) sent by the arduino

• pin_type: 0 for digital pin, 1 for analog pin, 2 for virtual pin
• pin_index: Index of the pin

Code 5: Register pin listener [5][6][pin_type][pin_index][interval (4 bytes UNSIGNED LITTLE ENDIAN)]

Makes the Arduino report the pin's reading every interval

• pin_type: 0 for digital pin, 1 for analog pin, 2 for virtual pin
• pin_index: Index of the pin
• interval: interval (in ms) at which the Arduino reads the pin (-1 means don't read, 0 means no interval but report on-change)

Code 6: Reset board state [6][0]

Resets all pin states