mirror of
https://github.com/tinygo-org/tinygo.git
synced 2026-08-07 20:43:40 +00:00
avr: add support for the digispark
Blinking the on-board LED works. Nothing else has been tested yet.
This commit is contained in:
Ayke van Laethem
@@ -0,0 +1,7 @@
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// +build attiny85,digispark
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package machine
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const (
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LED = 1
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)
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@@ -0,0 +1,262 @@
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// +build avr,atmega
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package machine
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import (
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"device/avr"
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)
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// Configure sets the pin to input or output.
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func (p GPIO) Configure(config GPIOConfig) {
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if config.Mode == GPIO_OUTPUT { // set output bit
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if p.Pin < 8 {
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*avr.DDRD |= 1 << p.Pin
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} else {
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*avr.DDRB |= 1 << (p.Pin - 8)
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}
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} else { // configure input: clear output bit
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if p.Pin < 8 {
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*avr.DDRD &^= 1 << p.Pin
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} else {
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*avr.DDRB &^= 1 << (p.Pin - 8)
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}
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}
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}
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// Set changes the value of the GPIO pin. The pin must be configured as output.
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func (p GPIO) Set(value bool) {
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if value { // set bits
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if p.Pin < 8 {
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*avr.PORTD |= 1 << p.Pin
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} else {
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*avr.PORTB |= 1 << (p.Pin - 8)
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}
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} else { // clear bits
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if p.Pin < 8 {
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*avr.PORTD &^= 1 << p.Pin
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} else {
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*avr.PORTB &^= 1 << (p.Pin - 8)
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}
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}
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}
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// Get returns the current value of a GPIO pin.
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func (p GPIO) Get() bool {
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if p.Pin < 8 {
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val := *avr.PIND & (1 << p.Pin)
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return (val > 0)
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} else {
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val := *avr.PINB & (1 << (p.Pin - 8))
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return (val > 0)
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}
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}
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// InitPWM initializes the registers needed for PWM.
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func InitPWM() {
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// use waveform generation
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*avr.TCCR0A |= avr.TCCR0A_WGM00
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// set timer 0 prescale factor to 64
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*avr.TCCR0B |= avr.TCCR0B_CS01 | avr.TCCR0B_CS00
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// set timer 1 prescale factor to 64
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*avr.TCCR1B |= avr.TCCR1B_CS11
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// put timer 1 in 8-bit phase correct pwm mode
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*avr.TCCR1A |= avr.TCCR1A_WGM10
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// set timer 2 prescale factor to 64
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*avr.TCCR2B |= avr.TCCR2B_CS22
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// configure timer 2 for phase correct pwm (8-bit)
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*avr.TCCR2A |= avr.TCCR2A_WGM20
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}
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// Configure configures a PWM pin for output.
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func (pwm PWM) Configure() {
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if pwm.Pin < 8 {
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*avr.DDRD |= 1 << pwm.Pin
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} else {
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*avr.DDRB |= 1 << (pwm.Pin - 8)
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}
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}
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// Set turns on the duty cycle for a PWM pin using the provided value. On the AVR this is normally a
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// 8-bit value ranging from 0 to 255.
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func (pwm PWM) Set(value uint16) {
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value8 := value >> 8
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switch pwm.Pin {
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case 3:
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// connect pwm to pin on timer 2, channel B
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*avr.TCCR2A |= avr.TCCR2A_COM2B1
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*avr.OCR2B = avr.RegValue(value8) // set pwm duty
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case 5:
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// connect pwm to pin on timer 0, channel B
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*avr.TCCR0A |= avr.TCCR0A_COM0B1
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*avr.OCR0B = avr.RegValue(value8) // set pwm duty
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case 6:
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// connect pwm to pin on timer 0, channel A
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*avr.TCCR0A |= avr.TCCR0A_COM0A1
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*avr.OCR0A = avr.RegValue(value8) // set pwm duty
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case 9:
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// connect pwm to pin on timer 1, channel A
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*avr.TCCR1A |= avr.TCCR1A_COM1A1
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// this is a 16-bit value, but we only currently allow the low order bits to be set
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*avr.OCR1AL = avr.RegValue(value8) // set pwm duty
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case 10:
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// connect pwm to pin on timer 1, channel B
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*avr.TCCR1A |= avr.TCCR1A_COM1B1
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// this is a 16-bit value, but we only currently allow the low order bits to be set
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*avr.OCR1BL = avr.RegValue(value8) // set pwm duty
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case 11:
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// connect pwm to pin on timer 2, channel A
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*avr.TCCR2A |= avr.TCCR2A_COM2A1
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*avr.OCR2A = avr.RegValue(value8) // set pwm duty
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default:
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panic("Invalid PWM pin")
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}
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}
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// I2CConfig is used to store config info for I2C.
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type I2CConfig struct {
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Frequency uint32
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}
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// Configure is intended to setup the I2C interface.
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func (i2c I2C) Configure(config I2CConfig) {
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// Default I2C bus speed is 100 kHz.
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if config.Frequency == 0 {
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config.Frequency = TWI_FREQ_100KHZ
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}
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// Activate internal pullups for twi.
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*avr.PORTC |= (avr.DIDR0_ADC4D | avr.DIDR0_ADC5D)
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// Initialize twi prescaler and bit rate.
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*avr.TWSR |= (avr.TWSR_TWPS0 | avr.TWSR_TWPS1)
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// twi bit rate formula from atmega128 manual pg. 204:
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// SCL Frequency = CPU Clock Frequency / (16 + (2 * TWBR))
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// NOTE: TWBR should be 10 or higher for master mode.
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// It is 72 for a 16mhz board with 100kHz TWI
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*avr.TWBR = avr.RegValue(((CPU_FREQUENCY / config.Frequency) - 16) / 2)
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// Enable twi module.
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*avr.TWCR = avr.TWCR_TWEN
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}
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// Tx does a single I2C transaction at the specified address.
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// It clocks out the given address, writes the bytes in w, reads back len(r)
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// bytes and stores them in r, and generates a stop condition on the bus.
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func (i2c I2C) Tx(addr uint16, w, r []byte) error {
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if len(w) != 0 {
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i2c.start(uint8(addr), true) // start transmission for writing
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for _, b := range w {
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i2c.writeByte(b)
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}
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}
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if len(r) != 0 {
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i2c.start(uint8(addr), false) // re-start transmission for reading
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for i := range r { // read each char
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r[i] = i2c.readByte()
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}
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}
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if len(w) != 0 || len(r) != 0 {
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// Stop the transmission after it has been started.
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i2c.stop()
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}
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return nil
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}
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// start starts an I2C communication session.
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func (i2c I2C) start(address uint8, write bool) {
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// Clear TWI interrupt flag, put start condition on SDA, and enable TWI.
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*avr.TWCR = (avr.TWCR_TWINT | avr.TWCR_TWSTA | avr.TWCR_TWEN)
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// Wait till start condition is transmitted.
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for (*avr.TWCR & avr.TWCR_TWINT) == 0 {
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}
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// Write 7-bit shifted peripheral address.
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address <<= 1
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if !write {
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address |= 1 // set read flag
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}
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i2c.writeByte(address)
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}
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// stop ends an I2C communication session.
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func (i2c I2C) stop() {
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// Send stop condition.
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*avr.TWCR = (avr.TWCR_TWEN | avr.TWCR_TWINT | avr.TWCR_TWSTO)
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// Wait for stop condition to be executed on bus.
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for (*avr.TWCR & avr.TWCR_TWSTO) == 0 {
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}
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}
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// writeByte writes a single byte to the I2C bus.
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func (i2c I2C) writeByte(data byte) {
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// Write data to register.
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*avr.TWDR = avr.RegValue(data)
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// Clear TWI interrupt flag and enable TWI.
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*avr.TWCR = (avr.TWCR_TWEN | avr.TWCR_TWINT)
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// Wait till data is transmitted.
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for (*avr.TWCR & avr.TWCR_TWINT) == 0 {
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}
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}
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// readByte reads a single byte from the I2C bus.
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func (i2c I2C) readByte() byte {
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// Clear TWI interrupt flag and enable TWI.
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*avr.TWCR = (avr.TWCR_TWEN | avr.TWCR_TWINT | avr.TWCR_TWEA)
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// Wait till read request is transmitted.
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for (*avr.TWCR & avr.TWCR_TWINT) == 0 {
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}
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return byte(*avr.TWDR)
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}
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// Configure the UART on the AVR. Defaults to 9600 baud on Arduino.
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func (uart UART) Configure(config UARTConfig) {
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if config.BaudRate == 0 {
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config.BaudRate = 9600
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}
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// Set baud rate based on prescale formula from
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// https://www.microchip.com/webdoc/AVRLibcReferenceManual/FAQ_1faq_wrong_baud_rate.html
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// ((F_CPU + UART_BAUD_RATE * 8L) / (UART_BAUD_RATE * 16L) - 1)
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ps := ((CPU_FREQUENCY+config.BaudRate*8)/(config.BaudRate*16) - 1)
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*avr.UBRR0H = avr.RegValue(ps >> 8)
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*avr.UBRR0L = avr.RegValue(ps & 0xff)
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// enable RX, TX and RX interrupt
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*avr.UCSR0B = avr.UCSR0B_RXEN0 | avr.UCSR0B_TXEN0 | avr.UCSR0B_RXCIE0
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// 8-bits data
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*avr.UCSR0C = avr.UCSR0C_UCSZ01 | avr.UCSR0C_UCSZ00
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}
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// WriteByte writes a byte of data to the UART.
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func (uart UART) WriteByte(c byte) error {
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// Wait until UART buffer is not busy.
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for (*avr.UCSR0A & avr.UCSR0A_UDRE0) == 0 {
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}
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*avr.UDR0 = avr.RegValue(c) // send char
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return nil
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}
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//go:interrupt USART_RX_vect
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func handleUSART_RX() {
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// Read register to clear it.
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data := *avr.UDR0
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// Ensure no error.
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if (*avr.UCSR0A & (avr.UCSR0A_FE0 | avr.UCSR0A_DOR0 | avr.UCSR0A_UPE0)) == 0 {
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// Put data from UDR register into buffer.
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bufferPut(byte(data))
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}
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}
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@@ -0,0 +1,48 @@
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// +build avr,attiny
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package machine
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import (
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"device/avr"
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)
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// Configure sets the pin to input or output.
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func (p GPIO) Configure(config GPIOConfig) {
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if config.Mode == GPIO_OUTPUT { // set output bit
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*avr.DDRB |= 1 << p.Pin
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} else { // configure input: clear output bit
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*avr.DDRB &^= 1 << p.Pin
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}
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}
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// Set changes the value of the GPIO pin. The pin must be configured as output.
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func (p GPIO) Set(value bool) {
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if value { // set bits
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*avr.PORTB |= 1 << p.Pin
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} else { // clear bits
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*avr.PORTB &^= 1 << p.Pin
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}
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}
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// Get returns the current value of a GPIO pin.
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func (p GPIO) Get() bool {
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val := *avr.PINB & (1 << p.Pin)
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return (val > 0)
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}
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// Configure is a dummy implementation. UART has not been implemented for ATtiny
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// devices.
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func (uart UART) Configure(config UARTConfig) {
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}
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// WriteByte is a dummy implementation. UART has not been implemented for ATtiny
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// devices.
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func (uart UART) WriteByte(c byte) error {
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return nil
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}
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// Tx is a dummy implementation. I2C has not been implemented for ATtiny
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// devices.
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func (i2c I2C) Tx(addr uint16, w, r []byte) error {
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return nil
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}
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+2
-255
@@ -13,115 +13,6 @@ const (
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GPIO_OUTPUT
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)
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func (p GPIO) Configure(config GPIOConfig) {
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if config.Mode == GPIO_OUTPUT { // set output bit
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if p.Pin < 8 {
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*avr.DDRD |= 1 << p.Pin
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} else {
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*avr.DDRB |= 1 << (p.Pin - 8)
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}
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} else { // configure input: clear output bit
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if p.Pin < 8 {
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*avr.DDRD &^= 1 << p.Pin
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} else {
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*avr.DDRB &^= 1 << (p.Pin - 8)
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}
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}
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}
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func (p GPIO) Set(value bool) {
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if value { // set bits
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if p.Pin < 8 {
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*avr.PORTD |= 1 << p.Pin
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} else {
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*avr.PORTB |= 1 << (p.Pin - 8)
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}
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} else { // clear bits
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if p.Pin < 8 {
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*avr.PORTD &^= 1 << p.Pin
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} else {
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*avr.PORTB &^= 1 << (p.Pin - 8)
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}
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}
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}
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// Get returns the current value of a GPIO pin.
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func (p GPIO) Get() bool {
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if p.Pin < 8 {
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val := *avr.PIND & (1 << p.Pin)
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return (val > 0)
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} else {
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val := *avr.PINB & (1 << (p.Pin - 8))
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return (val > 0)
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}
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}
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// InitPWM initializes the registers needed for PWM.
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func InitPWM() {
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// use waveform generation
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*avr.TCCR0A |= avr.TCCR0A_WGM00
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// set timer 0 prescale factor to 64
|
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*avr.TCCR0B |= avr.TCCR0B_CS01 | avr.TCCR0B_CS00
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// set timer 1 prescale factor to 64
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*avr.TCCR1B |= avr.TCCR1B_CS11
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// put timer 1 in 8-bit phase correct pwm mode
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*avr.TCCR1A |= avr.TCCR1A_WGM10
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// set timer 2 prescale factor to 64
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*avr.TCCR2B |= avr.TCCR2B_CS22
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// configure timer 2 for phase correct pwm (8-bit)
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*avr.TCCR2A |= avr.TCCR2A_WGM20
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}
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// Configure configures a PWM pin for output.
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func (pwm PWM) Configure() {
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if pwm.Pin < 8 {
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*avr.DDRD |= 1 << pwm.Pin
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} else {
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*avr.DDRB |= 1 << (pwm.Pin - 8)
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}
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}
|
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|
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// Set turns on the duty cycle for a PWM pin using the provided value. On the AVR this is normally a
|
||||
// 8-bit value ranging from 0 to 255.
|
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func (pwm PWM) Set(value uint16) {
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value8 := value >> 8
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switch pwm.Pin {
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case 3:
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// connect pwm to pin on timer 2, channel B
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*avr.TCCR2A |= avr.TCCR2A_COM2B1
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*avr.OCR2B = avr.RegValue(value8) // set pwm duty
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case 5:
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// connect pwm to pin on timer 0, channel B
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||||
*avr.TCCR0A |= avr.TCCR0A_COM0B1
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*avr.OCR0B = avr.RegValue(value8) // set pwm duty
|
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case 6:
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// connect pwm to pin on timer 0, channel A
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*avr.TCCR0A |= avr.TCCR0A_COM0A1
|
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*avr.OCR0A = avr.RegValue(value8) // set pwm duty
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||||
case 9:
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// connect pwm to pin on timer 1, channel A
|
||||
*avr.TCCR1A |= avr.TCCR1A_COM1A1
|
||||
// this is a 16-bit value, but we only currently allow the low order bits to be set
|
||||
*avr.OCR1AL = avr.RegValue(value8) // set pwm duty
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||||
case 10:
|
||||
// connect pwm to pin on timer 1, channel B
|
||||
*avr.TCCR1A |= avr.TCCR1A_COM1B1
|
||||
// this is a 16-bit value, but we only currently allow the low order bits to be set
|
||||
*avr.OCR1BL = avr.RegValue(value8) // set pwm duty
|
||||
case 11:
|
||||
// connect pwm to pin on timer 2, channel A
|
||||
*avr.TCCR2A |= avr.TCCR2A_COM2A1
|
||||
*avr.OCR2A = avr.RegValue(value8) // set pwm duty
|
||||
default:
|
||||
panic("Invalid PWM pin")
|
||||
}
|
||||
}
|
||||
|
||||
// InitADC initializes the registers needed for ADC.
|
||||
func InitADC() {
|
||||
// set a2d prescaler so we are inside the desired 50-200 KHz range at 16MHz.
|
||||
@@ -158,159 +49,15 @@ func (a ADC) Get() uint16 {
|
||||
return uint16(low) | uint16(high<<8)
|
||||
}
|
||||
|
||||
// I2C on the Arduino.
|
||||
// I2C on AVR.
|
||||
type I2C struct {
|
||||
}
|
||||
|
||||
// I2C0 is the only I2C interface on the Arduino.
|
||||
// I2C0 is the only I2C interface on most AVRs.
|
||||
var I2C0 = I2C{}
|
||||
|
||||
// I2CConfig is used to store config info for I2C.
|
||||
type I2CConfig struct {
|
||||
Frequency uint32
|
||||
}
|
||||
|
||||
// Configure is intended to setup the I2C interface.
|
||||
func (i2c I2C) Configure(config I2CConfig) {
|
||||
// Default I2C bus speed is 100 kHz.
|
||||
if config.Frequency == 0 {
|
||||
config.Frequency = TWI_FREQ_100KHZ
|
||||
}
|
||||
|
||||
// Activate internal pullups for twi.
|
||||
*avr.PORTC |= (avr.DIDR0_ADC4D | avr.DIDR0_ADC5D)
|
||||
|
||||
// Initialize twi prescaler and bit rate.
|
||||
*avr.TWSR |= (avr.TWSR_TWPS0 | avr.TWSR_TWPS1)
|
||||
|
||||
// twi bit rate formula from atmega128 manual pg. 204:
|
||||
// SCL Frequency = CPU Clock Frequency / (16 + (2 * TWBR))
|
||||
// NOTE: TWBR should be 10 or higher for master mode.
|
||||
// It is 72 for a 16mhz board with 100kHz TWI
|
||||
*avr.TWBR = avr.RegValue(((CPU_FREQUENCY / config.Frequency) - 16) / 2)
|
||||
|
||||
// Enable twi module.
|
||||
*avr.TWCR = avr.TWCR_TWEN
|
||||
}
|
||||
|
||||
// Tx does a single I2C transaction at the specified address.
|
||||
// It clocks out the given address, writes the bytes in w, reads back len(r)
|
||||
// bytes and stores them in r, and generates a stop condition on the bus.
|
||||
func (i2c I2C) Tx(addr uint16, w, r []byte) error {
|
||||
if len(w) != 0 {
|
||||
i2c.start(uint8(addr), true) // start transmission for writing
|
||||
for _, b := range w {
|
||||
i2c.writeByte(b)
|
||||
}
|
||||
}
|
||||
if len(r) != 0 {
|
||||
i2c.start(uint8(addr), false) // re-start transmission for reading
|
||||
for i := range r { // read each char
|
||||
r[i] = i2c.readByte()
|
||||
}
|
||||
}
|
||||
if len(w) != 0 || len(r) != 0 {
|
||||
// Stop the transmission after it has been started.
|
||||
i2c.stop()
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
// start starts an I2C communication session.
|
||||
func (i2c I2C) start(address uint8, write bool) {
|
||||
// Clear TWI interrupt flag, put start condition on SDA, and enable TWI.
|
||||
*avr.TWCR = (avr.TWCR_TWINT | avr.TWCR_TWSTA | avr.TWCR_TWEN)
|
||||
|
||||
// Wait till start condition is transmitted.
|
||||
for (*avr.TWCR & avr.TWCR_TWINT) == 0 {
|
||||
}
|
||||
|
||||
// Write 7-bit shifted peripheral address.
|
||||
address <<= 1
|
||||
if !write {
|
||||
address |= 1 // set read flag
|
||||
}
|
||||
i2c.writeByte(address)
|
||||
}
|
||||
|
||||
// stop ends an I2C communication session.
|
||||
func (i2c I2C) stop() {
|
||||
// Send stop condition.
|
||||
*avr.TWCR = (avr.TWCR_TWEN | avr.TWCR_TWINT | avr.TWCR_TWSTO)
|
||||
|
||||
// Wait for stop condition to be executed on bus.
|
||||
for (*avr.TWCR & avr.TWCR_TWSTO) == 0 {
|
||||
}
|
||||
}
|
||||
|
||||
// writeByte writes a single byte to the I2C bus.
|
||||
func (i2c I2C) writeByte(data byte) {
|
||||
// Write data to register.
|
||||
*avr.TWDR = avr.RegValue(data)
|
||||
|
||||
// Clear TWI interrupt flag and enable TWI.
|
||||
*avr.TWCR = (avr.TWCR_TWEN | avr.TWCR_TWINT)
|
||||
|
||||
// Wait till data is transmitted.
|
||||
for (*avr.TWCR & avr.TWCR_TWINT) == 0 {
|
||||
}
|
||||
}
|
||||
|
||||
// readByte reads a single byte from the I2C bus.
|
||||
func (i2c I2C) readByte() byte {
|
||||
// Clear TWI interrupt flag and enable TWI.
|
||||
*avr.TWCR = (avr.TWCR_TWEN | avr.TWCR_TWINT | avr.TWCR_TWEA)
|
||||
|
||||
// Wait till read request is transmitted.
|
||||
for (*avr.TWCR & avr.TWCR_TWINT) == 0 {
|
||||
}
|
||||
|
||||
return byte(*avr.TWDR)
|
||||
}
|
||||
|
||||
// UART
|
||||
var (
|
||||
// UART0 is the hardware serial port on the AVR.
|
||||
UART0 = &UART{}
|
||||
)
|
||||
|
||||
// Configure the UART on the AVR. Defaults to 9600 baud on Arduino.
|
||||
func (uart UART) Configure(config UARTConfig) {
|
||||
if config.BaudRate == 0 {
|
||||
config.BaudRate = 9600
|
||||
}
|
||||
|
||||
// Set baud rate based on prescale formula from
|
||||
// https://www.microchip.com/webdoc/AVRLibcReferenceManual/FAQ_1faq_wrong_baud_rate.html
|
||||
// ((F_CPU + UART_BAUD_RATE * 8L) / (UART_BAUD_RATE * 16L) - 1)
|
||||
ps := ((CPU_FREQUENCY+config.BaudRate*8)/(config.BaudRate*16) - 1)
|
||||
*avr.UBRR0H = avr.RegValue(ps >> 8)
|
||||
*avr.UBRR0L = avr.RegValue(ps & 0xff)
|
||||
|
||||
// enable RX, TX and RX interrupt
|
||||
*avr.UCSR0B = avr.UCSR0B_RXEN0 | avr.UCSR0B_TXEN0 | avr.UCSR0B_RXCIE0
|
||||
|
||||
// 8-bits data
|
||||
*avr.UCSR0C = avr.UCSR0C_UCSZ01 | avr.UCSR0C_UCSZ00
|
||||
}
|
||||
|
||||
// WriteByte writes a byte of data to the UART.
|
||||
func (uart UART) WriteByte(c byte) error {
|
||||
// Wait until UART buffer is not busy.
|
||||
for (*avr.UCSR0A & avr.UCSR0A_UDRE0) == 0 {
|
||||
}
|
||||
*avr.UDR0 = avr.RegValue(c) // send char
|
||||
return nil
|
||||
}
|
||||
|
||||
//go:interrupt USART_RX_vect
|
||||
func handleUSART_RX() {
|
||||
// Read register to clear it.
|
||||
data := *avr.UDR0
|
||||
|
||||
// Ensure no error.
|
||||
if (*avr.UCSR0A & (avr.UCSR0A_FE0 | avr.UCSR0A_DOR0 | avr.UCSR0A_UPE0)) == 0 {
|
||||
// Put data from UDR register into buffer.
|
||||
bufferPut(byte(data))
|
||||
}
|
||||
}
|
||||
|
||||
Reference in New Issue
Block a user