const HasLowFrequencyCrystal = true
The PineTime has a low-frequency (32kHz) crystal oscillator on board.
const (
LED = LED1
LED1 = LCD_BACKLIGHT_HIGH
LED2 = LCD_BACKLIGHT_MID
LED3 = LCD_BACKLIGHT_LOW
)
LEDs simply expose the three brightness level LEDs on the PineTime. They can be useful for simple “hello world” style programs.
const (
UART_TX_PIN Pin = 11 // TP29 (TXD)
UART_RX_PIN Pin = NoPin
)
UART pins for PineTime. Note that RX is set to NoPin as RXD is not listed in the PineTime schematic 1.0: http://files.pine64.org/doc/PineTime/PineTime%20Port%20Assignment%20rev1.0.pdf
const (
SPI0_SCK_PIN Pin = 2
SPI0_SDO_PIN Pin = 3
SPI0_SDI_PIN Pin = 4
)
SPI pins for the PineTime.
const (
SDA_PIN Pin = 6
SCL_PIN Pin = 7
)
I2C pins for the PineTime.
const (
BUTTON_IN Pin = 13
BUTTON_OUT Pin = 15
)
Button pins. For some reason, there are two pins for the button.
const VIBRATOR_PIN Pin = 16
Pin for the vibrator.
const (
LCD_SCK = SPI0_SCK_PIN
LCD_SDI = SPI0_SDO_PIN
LCD_RS Pin = 18
LCD_CS Pin = 25
LCD_RESET Pin = 26
LCD_BACKLIGHT_LOW Pin = 14
LCD_BACKLIGHT_MID Pin = 22
LCD_BACKLIGHT_HIGH Pin = 23
)
LCD pins, using the naming convention of the official docs: http://files.pine64.org/doc/PineTime/PineTime%20Port%20Assignment%20rev1.0.pdf
const (
TWI_FREQ_100KHZ = 100000
TWI_FREQ_400KHZ = 400000
)
TWI_FREQ is the I2C bus speed. Normally either 100 kHz, or 400 kHz for high-speed bus.
const NoPin = Pin(0xff)
NoPin explicitly indicates “not a pin”. Use this pin if you want to leave one of the pins in a peripheral unconfigured (if supported by the hardware).
const (
PinInput PinMode = (nrf.GPIO_PIN_CNF_DIR_Input << nrf.GPIO_PIN_CNF_DIR_Pos) | (nrf.GPIO_PIN_CNF_INPUT_Connect << nrf.GPIO_PIN_CNF_INPUT_Pos)
PinInputPullup PinMode = PinInput | (nrf.GPIO_PIN_CNF_PULL_Pullup << nrf.GPIO_PIN_CNF_PULL_Pos)
PinInputPulldown PinMode = PinInput | (nrf.GPIO_PIN_CNF_PULL_Pulldown << nrf.GPIO_PIN_CNF_PULL_Pos)
PinOutput PinMode = (nrf.GPIO_PIN_CNF_DIR_Output << nrf.GPIO_PIN_CNF_DIR_Pos) | (nrf.GPIO_PIN_CNF_INPUT_Disconnect << nrf.GPIO_PIN_CNF_INPUT_Pos)
)
const (
PinRising PinChange = nrf.GPIOTE_CONFIG_POLARITY_LoToHi
PinFalling PinChange = nrf.GPIOTE_CONFIG_POLARITY_HiToLo
PinToggle PinChange = nrf.GPIOTE_CONFIG_POLARITY_Toggle
)
Pin change interrupt constants for SetInterrupt.
var (
ErrInvalidInputPin = errors.New("machine: invalid input pin")
ErrInvalidOutputPin = errors.New("machine: invalid output pin")
ErrInvalidClockPin = errors.New("machine: invalid clock pin")
ErrInvalidDataPin = errors.New("machine: invalid data pin")
ErrNoPinChangeChannel = errors.New("machine: no channel available for pin interrupt")
)
var (
ErrTxInvalidSliceSize = errors.New("SPI write and read slices must be same size")
)
var (
// NRF_UART0 is the hardware UART on the NRF SoC.
NRF_UART0 = UART{Buffer: NewRingBuffer()}
)
UART
var (
I2C0 = I2C{Bus: nrf.TWI0}
I2C1 = I2C{Bus: nrf.TWI1}
)
There are 2 I2C interfaces on the NRF.
var (
SPI0 = SPI{Bus: nrf.SPI0}
SPI1 = SPI{Bus: nrf.SPI1}
)
There are 2 SPI interfaces on the NRF5x.
var (
UART0 = NRF_UART0
)
func CPUFrequency() uint32
func InitADC()
InitADC initializes the registers needed for ADC.
func InitPWM()
InitPWM initializes the registers needed for PWM.
func NewRingBuffer() *RingBuffer
NewRingBuffer returns a new ring buffer.
type ADC struct {
Pin Pin
}
func (a ADC) Configure()
Configure configures an ADC pin to be able to read analog data.
func (a ADC) Get() uint16
Get returns the current value of a ADC pin in the range 0..0xffff.
type I2C struct {
Bus *nrf.TWI_Type
}
I2C on the NRF.
func (i2c I2C) Configure(config I2CConfig)
Configure is intended to setup the I2C interface.
func (i2c I2C) ReadRegister(address uint8, register uint8, data []byte) error
ReadRegister transmits the register, restarts the connection as a read operation, and reads the response.
Many I2C-compatible devices are organized in terms of registers. This method is a shortcut to easily read such registers. Also, it only works for devices with 7-bit addresses, which is the vast majority.
func (i2c I2C) Tx(addr uint16, w, r []byte) error
Tx does a single I2C transaction at the specified address. It clocks out the given address, writes the bytes in w, reads back len® bytes and stores them in r, and generates a stop condition on the bus.
func (i2c I2C) WriteRegister(address uint8, register uint8, data []byte) error
WriteRegister transmits first the register and then the data to the peripheral device.
Many I2C-compatible devices are organized in terms of registers. This method is a shortcut to easily write to such registers. Also, it only works for devices with 7-bit addresses, which is the vast majority.
type I2CConfig struct {
Frequency uint32
SCL Pin
SDA Pin
}
I2CConfig is used to store config info for I2C.
type PWM struct {
Pin Pin
}
func (pwm PWM) Configure() error
Configure configures a PWM pin for output.
func (pwm PWM) Set(value uint16)
Set turns on the duty cycle for a PWM pin using the provided value.
type Pin uint8
Pin is a single pin on a chip, which may be connected to other hardware devices. It can either be used directly as GPIO pin or it can be used in other peripherals like ADC, I2C, etc.
func (p Pin) Configure(config PinConfig)
Configure this pin with the given configuration.
func (p Pin) Get() bool
Get returns the current value of a GPIO pin.
func (p Pin) High()
High sets this GPIO pin to high, assuming it has been configured as an output pin. It is hardware dependent (and often undefined) what happens if you set a pin to high that is not configured as an output pin.
func (p Pin) Low()
Low sets this GPIO pin to low, assuming it has been configured as an output pin. It is hardware dependent (and often undefined) what happens if you set a pin to low that is not configured as an output pin.
func (p Pin) PortMaskClear() (*uint32, uint32)
Return the register and mask to disable a given port. This can be used to implement bit-banged drivers.
func (p Pin) PortMaskSet() (*uint32, uint32)
Return the register and mask to enable a given GPIO pin. This can be used to implement bit-banged drivers.
func (p Pin) Set(high bool)
Set the pin to high or low. Warning: only use this on an output pin!
func (p Pin) SetInterrupt(change PinChange, callback func(Pin)) error
SetInterrupt sets an interrupt to be executed when a particular pin changes state.
This call will replace a previously set callback on this pin. You can pass a nil func to unset the pin change interrupt. If you do so, the change parameter is ignored and can be set to any value (such as 0).
type PinChange uint8
type PinConfig struct {
Mode PinMode
}
type PinMode uint8
type RingBuffer struct {
rxbuffer [bufferSize]volatile.Register8
head volatile.Register8
tail volatile.Register8
}
RingBuffer is ring buffer implementation inspired by post at https://www.embeddedrelated.com/showthread/comp.arch.embedded/77084-1.php
func (rb *RingBuffer) Clear()
Clear resets the head and tail pointer to zero.
func (rb *RingBuffer) Get() (byte, bool)
Get returns a byte from the buffer. If the buffer is empty, the method will return a false as the second value.
func (rb *RingBuffer) Put(val byte) bool
Put stores a byte in the buffer. If the buffer is already full, the method will return false.
func (rb *RingBuffer) Used() uint8
Used returns how many bytes in buffer have been used.
type SPI struct {
Bus *nrf.SPI_Type
}
SPI on the NRF.
func (spi SPI) Configure(config SPIConfig)
Configure is intended to setup the SPI interface.
func (spi SPI) Transfer(w byte) (byte, error)
Transfer writes/reads a single byte using the SPI interface.
func (spi SPI) Tx(w, r []byte) error
Tx handles read/write operation for SPI interface. Since SPI is a syncronous write/read interface, there must always be the same number of bytes written as bytes read. The Tx method knows about this, and offers a few different ways of calling it.
This form sends the bytes in tx buffer, putting the resulting bytes read into the rx buffer. Note that the tx and rx buffers must be the same size:
spi.Tx(tx, rx)
This form sends the tx buffer, ignoring the result. Useful for sending “commands” that return zeros until all the bytes in the command packet have been received:
spi.Tx(tx, nil)
This form sends zeros, putting the result into the rx buffer. Good for reading a “result packet”:
spi.Tx(nil, rx)
type SPIConfig struct {
Frequency uint32
SCK Pin
SDO Pin
SDI Pin
LSBFirst bool
Mode uint8
}
SPIConfig is used to store config info for SPI.
type UART struct {
Buffer *RingBuffer
}
UART on the NRF.
func (uart UART) Buffered() int
Buffered returns the number of bytes currently stored in the RX buffer.
func (uart UART) Configure(config UARTConfig)
Configure the UART.
func (uart UART) Read(data []byte) (n int, err error)
Read from the RX buffer.
func (uart UART) ReadByte() (byte, error)
ReadByte reads a single byte from the RX buffer. If there is no data in the buffer, returns an error.
func (uart UART) Receive(data byte)
Receive handles adding data to the UART’s data buffer. Usually called by the IRQ handler for a machine.
func (uart UART) SetBaudRate(br uint32)
SetBaudRate sets the communication speed for the UART.
func (uart UART) Write(data []byte) (n int, err error)
Write data to the UART.
func (uart UART) WriteByte(c byte) error
WriteByte writes a byte of data to the UART.
type UARTConfig struct {
BaudRate uint32
TX Pin
RX Pin
}