seesaw.py

# SPDX-FileCopyrightText: 2017 Dean Miller for Adafruit Industries
#
# SPDX-License-Identifier: MIT

"""
`adafruit_seesaw.seesaw`
====================================================

An I2C to whatever helper chip.

* Author(s): Dean Miller

Implementation Notes
--------------------

**Hardware:**

* Adafruit `ATSAMD09 Breakout with seesaw
  <https://www.adafruit.com/product/3657>`_ (Product ID: 3657)

**Software and Dependencies:**

* Adafruit CircuitPython firmware: https://circuitpython.org/
* or Adafruit Blinka: https://circuitpython.org/blinka
* Adafruit's Bus Device library: https://github.com/adafruit/Adafruit_CircuitPython_BusDevice
"""

# This code needs to be broken up into analogio, busio, digitalio, and pulseio
# compatible classes so we won't bother with some lints until then.
# pylint: disable=missing-docstring,invalid-name,too-many-public-methods,no-name-in-module

import time

try:
    import struct
except ImportError:
    import ustruct as struct
try:
    from micropython import const
except ImportError:

    def const(x):
        return x


from adafruit_bus_device.i2c_device import I2CDevice

__version__ = "0.0.0-auto.0"
__repo__ = "https://github.com/adafruit/Adafruit_CircuitPython_seesaw.git"

_STATUS_BASE = const(0x00)

_GPIO_BASE = const(0x01)
_SERCOM0_BASE = const(0x02)

_TIMER_BASE = const(0x08)
_ADC_BASE = const(0x09)
_DAC_BASE = const(0x0A)
_INTERRUPT_BASE = const(0x0B)
_DAP_BASE = const(0x0C)
_EEPROM_BASE = const(0x0D)
_NEOPIXEL_BASE = const(0x0E)
_TOUCH_BASE = const(0x0F)
_ENCODER_BASE = const(0x11)

_GPIO_DIRSET_BULK = const(0x02)
_GPIO_DIRCLR_BULK = const(0x03)
_GPIO_BULK = const(0x04)
_GPIO_BULK_SET = const(0x05)
_GPIO_BULK_CLR = const(0x06)
_GPIO_BULK_TOGGLE = const(0x07)
_GPIO_INTENSET = const(0x08)
_GPIO_INTENCLR = const(0x09)
_GPIO_INTFLAG = const(0x0A)
_GPIO_PULLENSET = const(0x0B)
_GPIO_PULLENCLR = const(0x0C)

_STATUS_HW_ID = const(0x01)
_STATUS_VERSION = const(0x02)
_STATUS_OPTIONS = const(0x03)
_STATUS_TEMP = const(0x04)
_STATUS_SWRST = const(0x7F)

_TIMER_STATUS = const(0x00)
_TIMER_PWM = const(0x01)
_TIMER_FREQ = const(0x02)

_ADC_STATUS = const(0x00)
_ADC_INTEN = const(0x02)
_ADC_INTENCLR = const(0x03)
_ADC_WINMODE = const(0x04)
_ADC_WINTHRESH = const(0x05)
_ADC_CHANNEL_OFFSET = const(0x07)

_SERCOM_STATUS = const(0x00)
_SERCOM_INTEN = const(0x02)
_SERCOM_INTENCLR = const(0x03)
_SERCOM_BAUD = const(0x04)
_SERCOM_DATA = const(0x05)

_NEOPIXEL_STATUS = const(0x00)
_NEOPIXEL_PIN = const(0x01)
_NEOPIXEL_SPEED = const(0x02)
_NEOPIXEL_BUF_LENGTH = const(0x03)
_NEOPIXEL_BUF = const(0x04)
_NEOPIXEL_SHOW = const(0x05)

_TOUCH_CHANNEL_OFFSET = const(0x10)

_HW_ID_CODE = const(0x55)
_EEPROM_I2C_ADDR = const(0x3F)

_ENCODER_STATUS = const(0x00)
_ENCODER_INTENSET = const(0x10)
_ENCODER_INTENCLR = const(0x20)
_ENCODER_POSITION = const(0x30)
_ENCODER_DELTA = const(0x40)

# TODO: update when we get real PID
_CRICKIT_PID = const(9999)
_ROBOHATMM1_PID = const(9998)


class Seesaw:
    """Driver for Seesaw i2c generic conversion trip

    :param ~busio.I2C i2c_bus: Bus the SeeSaw is connected to
    :param int addr: I2C address of the SeeSaw device
    :param ~digitalio.DigitalInOut drdy: Pin connected to SeeSaw's 'ready' output"""

    INPUT = const(0x00)
    OUTPUT = const(0x01)
    INPUT_PULLUP = const(0x02)
    INPUT_PULLDOWN = const(0x03)

    def __init__(self, i2c_bus, addr=0x49, drdy=None):
        self._drdy = drdy
        if drdy is not None:
            drdy.switch_to_input()

        self.i2c_device = I2CDevice(i2c_bus, addr)
        self.sw_reset()

    def sw_reset(self):
        """Trigger a software reset of the SeeSaw chip"""
        self.write8(_STATUS_BASE, _STATUS_SWRST, 0xFF)
        time.sleep(0.500)

        chip_id = self.read8(_STATUS_BASE, _STATUS_HW_ID)

        if chip_id != _HW_ID_CODE:
            raise RuntimeError(
                "Seesaw hardware ID returned (0x{:x}) is not "
                "correct! Expected 0x{:x}. Please check your wiring.".format(
                    chip_id, _HW_ID_CODE
                )
            )

        pid = self.get_version() >> 16
        # pylint: disable=import-outside-toplevel
        if pid == _CRICKIT_PID:
            from adafruit_seesaw.crickit import Crickit_Pinmap

            self.pin_mapping = Crickit_Pinmap
        elif pid == _ROBOHATMM1_PID:
            from adafruit_seesaw.robohat import MM1_Pinmap

            self.pin_mapping = MM1_Pinmap
        else:
            from adafruit_seesaw.samd09 import SAMD09_Pinmap

            self.pin_mapping = SAMD09_Pinmap
        # pylint: enable=import-outside-toplevel

    def get_options(self):
        """Retrieve the 'options' word from the SeeSaw board"""
        buf = bytearray(4)
        self.read(_STATUS_BASE, _STATUS_OPTIONS, buf)
        ret = struct.unpack(">I", buf)[0]
        return ret

    def get_version(self):
        """Retrieve the 'version' word from the SeeSaw board"""
        buf = bytearray(4)
        self.read(_STATUS_BASE, _STATUS_VERSION, buf)
        ret = struct.unpack(">I", buf)[0]
        return ret

    def pin_mode(self, pin, mode):
        """Set the mode of a pin by number"""
        if pin >= 32:
            self.pin_mode_bulk_b(1 << (pin - 32), mode)
        else:
            self.pin_mode_bulk(1 << pin, mode)

    def digital_write(self, pin, value):
        """Set the value of an output pin by number"""
        if pin >= 32:
            self.digital_write_bulk_b(1 << (pin - 32), value)
        else:
            self.digital_write_bulk(1 << pin, value)

    def digital_read(self, pin):
        """Get the value of an input pin by number"""
        if pin >= 32:
            return self.digital_read_bulk_b((1 << (pin - 32))) != 0
        return self.digital_read_bulk((1 << pin)) != 0

    def digital_read_bulk(self, pins, delay=0.008):
        """Get the values of all the pins on the 'A' port as a bitmask"""
        buf = bytearray(4)
        self.read(_GPIO_BASE, _GPIO_BULK, buf, delay=delay)
        buf[0] = buf[0] & 0x3F
        ret = struct.unpack(">I", buf)[0]
        return ret & pins

    def digital_read_bulk_b(self, pins, delay=0.008):
        """Get the values of all the pins on the 'B' port as a bitmask"""
        buf = bytearray(8)
        self.read(_GPIO_BASE, _GPIO_BULK, buf, delay=delay)
        ret = struct.unpack(">I", buf[4:])[0]
        return ret & pins

    def set_GPIO_interrupts(self, pins, enabled):
        """Enable or disable the GPIO interrupt"""
        cmd = struct.pack(">I", pins)
        if enabled:
            self.write(_GPIO_BASE, _GPIO_INTENSET, cmd)
        else:
            self.write(_GPIO_BASE, _GPIO_INTENCLR, cmd)

    def get_GPIO_interrupt_flag(self, delay=0.008):
        """Read and clear GPIO interrupts that have fired"""
        buf = bytearray(4)
        self.read(_GPIO_BASE, _GPIO_INTFLAG, buf, delay=delay)
        return struct.unpack(">I", buf)[0]

    def analog_read(self, pin):
        """Read the value of an analog pin by number"""
        buf = bytearray(2)
        if pin not in self.pin_mapping.analog_pins:
            raise ValueError("Invalid ADC pin")

        self.read(
            _ADC_BASE,
            _ADC_CHANNEL_OFFSET + self.pin_mapping.analog_pins.index(pin),
            buf,
        )
        ret = struct.unpack(">H", buf)[0]
        time.sleep(0.001)
        return ret

    def touch_read(self, pin):
        """Read the value of a touch pin by number"""
        buf = bytearray(2)

        if pin not in self.pin_mapping.touch_pins:
            raise ValueError("Invalid touch pin")

        self.read(
            _TOUCH_BASE,
            _TOUCH_CHANNEL_OFFSET + self.pin_mapping.touch_pins.index(pin),
            buf,
        )
        ret = struct.unpack(">H", buf)[0]
        return ret

    def moisture_read(self):
        """Read the value of the moisture sensor"""
        buf = bytearray(2)

        self.read(_TOUCH_BASE, _TOUCH_CHANNEL_OFFSET, buf, 0.005)
        ret = struct.unpack(">H", buf)[0]
        time.sleep(0.001)

        # retry if reading was bad
        count = 0
        while ret > 4095:
            self.read(_TOUCH_BASE, _TOUCH_CHANNEL_OFFSET, buf, 0.005)
            ret = struct.unpack(">H", buf)[0]
            time.sleep(0.001)
            count += 1
            if count > 3:
                raise RuntimeError("Could not get a valid moisture reading.")

        return ret

    def _pin_mode_bulk_x(self, capacity, offset, pins, mode):
        cmd = bytearray(capacity)
        cmd[offset:] = struct.pack(">I", pins)
        if mode == self.OUTPUT:
            self.write(_GPIO_BASE, _GPIO_DIRSET_BULK, cmd)
        elif mode == self.INPUT:
            self.write(_GPIO_BASE, _GPIO_DIRCLR_BULK, cmd)
            self.write(_GPIO_BASE, _GPIO_PULLENCLR, cmd)

        elif mode == self.INPUT_PULLUP:
            self.write(_GPIO_BASE, _GPIO_DIRCLR_BULK, cmd)
            self.write(_GPIO_BASE, _GPIO_PULLENSET, cmd)
            self.write(_GPIO_BASE, _GPIO_BULK_SET, cmd)

        elif mode == self.INPUT_PULLDOWN:
            self.write(_GPIO_BASE, _GPIO_DIRCLR_BULK, cmd)
            self.write(_GPIO_BASE, _GPIO_PULLENSET, cmd)
            self.write(_GPIO_BASE, _GPIO_BULK_CLR, cmd)

        else:
            raise ValueError("Invalid pin mode")

    def pin_mode_bulk(self, pins, mode):
        """Set the mode of all the pins on the 'A' port as a bitmask"""
        self._pin_mode_bulk_x(4, 0, pins, mode)

    def pin_mode_bulk_b(self, pins, mode):
        """Set the mode of all the pins on the 'B' port as a bitmask"""
        self._pin_mode_bulk_x(8, 4, pins, mode)

    def digital_write_bulk(self, pins, value):
        """Set the mode of pins on the 'A' port as a bitmask"""
        cmd = struct.pack(">I", pins)
        if value:
            self.write(_GPIO_BASE, _GPIO_BULK_SET, cmd)
        else:
            self.write(_GPIO_BASE, _GPIO_BULK_CLR, cmd)

    def digital_write_bulk_b(self, pins, value):
        """Set the mode of pins on the 'B' port as a bitmask"""
        cmd = bytearray(8)
        cmd[4:] = struct.pack(">I", pins)
        if value:
            self.write(_GPIO_BASE, _GPIO_BULK_SET, cmd)
        else:
            self.write(_GPIO_BASE, _GPIO_BULK_CLR, cmd)

    def analog_write(self, pin, value):
        """Set the value of an analog output by number"""
        pin_found = False
        if self.pin_mapping.pwm_width == 16:
            if pin in self.pin_mapping.pwm_pins:
                pin_found = True
                cmd = bytearray(
                    [self.pin_mapping.pwm_pins.index(pin), (value >> 8), value & 0xFF]
                )
        else:
            if pin in self.pin_mapping.pwm_pins:
                pin_found = True
                cmd = bytearray([self.pin_mapping.pwm_pins.index(pin), value])

        if pin_found is False:
            raise ValueError("Invalid PWM pin")
        self.write(_TIMER_BASE, _TIMER_PWM, cmd)
        time.sleep(0.001)

    def get_temp(self):
        """Read the temperature"""
        buf = bytearray(4)
        self.read(_STATUS_BASE, _STATUS_TEMP, buf, 0.005)
        buf[0] = buf[0] & 0x3F
        ret = struct.unpack(">I", buf)[0]
        return 0.00001525878 * ret

    def set_pwm_freq(self, pin, freq):
        """Set the PWM frequency of a pin by number"""
        if pin in self.pin_mapping.pwm_pins:
            cmd = bytearray(
                [self.pin_mapping.pwm_pins.index(pin), (freq >> 8), freq & 0xFF]
            )
            self.write(_TIMER_BASE, _TIMER_FREQ, cmd)
        else:
            raise ValueError("Invalid PWM pin")

    def encoder_position(self, encoder=0):
        """The current position of the encoder"""
        buf = bytearray(4)
        self.read(_ENCODER_BASE, _ENCODER_POSITION + encoder, buf)
        return struct.unpack(">i", buf)[0]

    def set_encoder_position(self, pos, encoder=0):
        """Set the current position of the encoder"""
        cmd = struct.pack(">i", pos)
        self.write(_ENCODER_BASE, _ENCODER_POSITION + encoder, cmd)

    def encoder_delta(self, encoder=0):
        """The change in encoder position since it was last read"""
        buf = bytearray(4)
        self.read(_ENCODER_BASE, _ENCODER_DELTA + encoder, buf)
        return struct.unpack(">i", buf)[0]

    def enable_encoder_interrupt(self, encoder=0):
        """Enable the interrupt to fire when the encoder changes position"""
        self.write8(_ENCODER_BASE, _ENCODER_INTENSET + encoder, 0x01)

    def disable_encoder_interrupt(self, encoder=0):
        """Disable the interrupt from firing when the encoder changes"""
        self.write8(_ENCODER_BASE, _ENCODER_INTENCLR + encoder, 0x01)

    # def enable_sercom_data_rdy_interrupt(self, sercom):
    #
    #     _sercom_inten.DATA_RDY = 1
    #     self.write8(SEESAW_SERCOM0_BASE + sercom, SEESAW_SERCOM_INTEN, _sercom_inten.get())
    #
    #
    # def disable_sercom_data_rdy_interrupt(self, sercom):
    #
    #     _sercom_inten.DATA_RDY = 0
    #     self.write8(SEESAW_SERCOM0_BASE + sercom, SEESAW_SERCOM_INTEN, _sercom_inten.get())
    #
    #
    # def read_sercom_data(self, sercom):
    #
    #     return self.read8(SEESAW_SERCOM0_BASE + sercom, SEESAW_SERCOM_DATA)

    def set_i2c_addr(self, addr):
        """Store a new address in the device's EEPROM and reboot it."""
        self.eeprom_write8(_EEPROM_I2C_ADDR, addr)
        time.sleep(0.250)
        self.i2c_device.device_address = addr
        self.sw_reset()

    def get_i2c_addr(self):
        """Return the device's I2C address stored in its EEPROM"""
        return self.read8(_EEPROM_BASE, _EEPROM_I2C_ADDR)

    def eeprom_write8(self, addr, val):
        """Write a single byte directly to the device's EEPROM"""
        self.eeprom_write(addr, bytearray([val]))

    def eeprom_write(self, addr, buf):
        """Write multiple bytes directly to the device's EEPROM"""
        self.write(_EEPROM_BASE, addr, buf)

    def eeprom_read8(self, addr):
        """Read a single byte directly to the device's EEPROM"""
        return self.read8(_EEPROM_BASE, addr)

    def uart_set_baud(self, baud):
        """Set the serial baudrate of the device"""
        cmd = struct.pack(">I", baud)
        self.write(_SERCOM0_BASE, _SERCOM_BAUD, cmd)

    def write8(self, reg_base, reg, value):
        """Write an arbitrary I2C byte register on the device"""
        self.write(reg_base, reg, bytearray([value]))

    def read8(self, reg_base, reg):
        """Read an arbitrary I2C byte register on the device"""
        ret = bytearray(1)
        self.read(reg_base, reg, ret)
        return ret[0]

    def read(self, reg_base, reg, buf, delay=0.008):
        """Read an arbitrary I2C register range on the device"""
        self.write(reg_base, reg)
        if self._drdy is not None:
            while self._drdy.value is False:
                pass
        else:
            time.sleep(delay)
        with self.i2c_device as i2c:
            i2c.readinto(buf)

    def write(self, reg_base, reg, buf=None):
        """Write an arbitrary I2C register range on the device"""
        full_buffer = bytearray([reg_base, reg])
        if buf is not None:
            full_buffer += buf

        if self._drdy is not None:
            while self._drdy.value is False:
                pass
        with self.i2c_device as i2c:
            i2c.write(full_buffer)