BCI firmware

import time
import digitalio
import busio
import board
import binascii

VERBOSE = True

WAKEUP = 0x02
STANDBY = 0x04
RESET = 0x06
START = 0x08
STOP = 0x0A
RDATAC = 0x10
SDATAC = 0x11
RDATA = 0x12

ID = 0x00
CONFIG1 = 0x01
CONFIG2 = 0x02
CONFIG3 = 0x03
CH1SET = 0x05
CH2SET = 0x06
CH3SET = 0x07
CH4SET = 0x08
CH5SET = 0x09
CH6SET = 0x0A
CH7SET = 0x0B
CH8SET = 0x0C


def delay(ms: float):
    time.sleep(ms / 1000)


def delay_microseconds(microseconds: float):
    time.sleep(microseconds / 1000000)


class ADS1299:
    def __init__(
        self, drdy, rst, cs, freq, sck, mosi, miso
    ):
        delay(50)

        self.rst = digitalio.DigitalInOut(rst)
        self.rst.direction = digitalio.Direction.OUTPUT
        self.rst.value = False
        delay_microseconds(4)  # Toggle reset pin
        self.rst.value = True
        delay_microseconds(20)  # Recommended to wait 18 tCLK before using device (~8uS)

        # SPI setup
        self.cs = digitalio.DigitalInOut(cs)
        self.cs.direction = digitalio.Direction.OUTPUT

        # self.sck.value = False
        self.cs.value = True

        # Set as master and enable SPI
        self.spi = busio.SPI(sck, MISO=miso, MOSI=mosi)  # SPI bus
        while not self.spi.try_lock():
            pass
        self.spi.configure(baudrate=9600, phase=1, polarity=0)

        # End of SPI setup

        # Initialize the data ready chip select and reset pins
        self.drdy = digitalio.DigitalInOut(drdy)
        self.drdy.direction = digitalio.Direction.INPUT

        self.cs.value = True
        self.rst.value = True

    def transfer(self, data: bytearray):
        # SPI communication methods
        # cli() and sei() in Arduino
        data_received = bytearray(1)
        self.spi.write_readinto(bytearray([data]), data_received)
        return data_received

    def wakeup(self):
        self.cs.value = False
        self.transfer(WAKEUP)
        self.cs.value = True
        delay_microseconds(
            3
        )  # Must wait 4 tCLK cycles before sending another command (Datasheet, pg. 35)

    def standby(self):
        # Only allowed to send WAKEUP after sending STANDBY
        self.cs.value = False
        self.transfer(STANDBY)
        self.cs.value = True

    def reset(self):
        # Reset all the registers to default settings
        self.cs.value = False
        self.transfer(RESET)
        delay_microseconds(
            12
        )  # Must wait 18 tCLK cycles to execute this command - page 35
        self.cs.value = True

    def start(self):
        # Start data conversion
        self.cs.value = False
        self.transfer(START)
        self.cs.value = True

    def stop(self):
        # Stop data conversion
        self.cs.value = False
        self.transfer(STOP)
        self.cs.value = True

    def rdatac(self):
        self.cs.value = False
        self.transfer(RDATAC)
        self.cs.value = True
        delay_microseconds(3)

    def sdatac(self):
        self.cs.value = False
        self.transfer(SDATAC)
        self.cs.value = True
        delay_microseconds(3)

    def rreg(self, address):
        # Reads ONE register at address
        opcode1 = address + 0x20  # RREG expects 001rrrrr where rrrrr = _address
        self.cs.value = False
        self.transfer(opcode1)
        self.transfer(0x00)  # Size to read = # of registers - 1
        result = self.transfer(0x00)
        self.cs.value = True
        if VERBOSE:
            print(f"Reading {address}: {result}")
        return result

    def rregs():
        pass

    def wreg(self, address: bytes, value: bytes):
        # Write one register at address
        opcode1 = address + 0x40  # WREG expects 010rrrrr where rrrrr = _address
        self.cs.value = False
        self.transfer(opcode1)
        self.transfer(0x00)
        self.transfer(value)
        self.cs.value = True
        if VERBOSE:
            print(f"Write register {address}: {value}")

    def wregs(self, address: bytes, registers_minus_one: bytes):
        pass

    def rdata(self):
        # Read data
        pass

    def get_device_id(self):
        # Simple check
        data = self.rreg(ID)
        if VERBOSE:
            print("Device ID: ", data)
        return data


if __name__ == "__main__":
    device = ADS1299(board.IO2, board.IO1, board.IO10, 0, board.IO12, board.IO13, board.IO11)
    device.get_device_id()