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deadprogram
94 lines
1.9 KiB
Go
94 lines
1.9 KiB
Go
// Package mcp3008 implements a driver for the MCP3008 Analog to Digital Converter.
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//
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// Datasheet: http://ww1.microchip.com/downloads/en/DeviceDoc/21295d.pdf
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package mcp3008 // import "tinygo.org/x/drivers/mcp3008"
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import (
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"errors"
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"machine"
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"tinygo.org/x/drivers"
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)
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// Device wraps MCP3008 SPI ADC.
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type Device struct {
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bus drivers.SPI
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cs machine.Pin
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tx []byte
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rx []byte
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CH0 ADCPin
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CH1 ADCPin
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CH2 ADCPin
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CH3 ADCPin
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CH4 ADCPin
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CH5 ADCPin
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CH6 ADCPin
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CH7 ADCPin
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}
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// ADCPin is the implementation of the ADConverter interface.
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type ADCPin struct {
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machine.Pin
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d *Device
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}
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// New returns a new MCP3008 driver. Pass in a fully configured SPI bus.
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func New(b drivers.SPI, csPin machine.Pin) *Device {
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d := &Device{bus: b,
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cs: csPin,
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tx: make([]byte, 3),
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rx: make([]byte, 3),
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}
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// setup all channels
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d.CH0 = d.GetADC(0)
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d.CH1 = d.GetADC(1)
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d.CH2 = d.GetADC(2)
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d.CH3 = d.GetADC(3)
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d.CH4 = d.GetADC(4)
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d.CH5 = d.GetADC(5)
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d.CH6 = d.GetADC(6)
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d.CH7 = d.GetADC(7)
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return d
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}
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// Configure sets up the device for communication
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func (d *Device) Configure() {
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d.cs.Configure(machine.PinConfig{Mode: machine.PinOutput})
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}
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// Read analog data from channel
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func (d *Device) Read(ch int) (uint16, error) {
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if ch < 0 || ch > 7 {
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return 0, errors.New("invalid channel for MCP3008 Read")
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}
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return d.GetADC(ch).Get(), nil
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}
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// GetADC returns an ADC for a specific channel.
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func (d *Device) GetADC(ch int) ADCPin {
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return ADCPin{machine.Pin(ch), d}
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}
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// Get the current reading for a specific ADCPin.
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func (p ADCPin) Get() uint16 {
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p.d.tx[0] = 0x01
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p.d.tx[1] = byte(8+p.Pin) << 4
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p.d.tx[2] = 0x00
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p.d.cs.Low()
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p.d.bus.Tx(p.d.tx, p.d.rx)
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// scale result to 16bit value like other ADCs
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result := uint16((p.d.rx[1]&0x3))<<(8+6) + uint16(p.d.rx[2])<<6
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p.d.cs.High()
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return result
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}
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// Configure here just for interface compatibility.
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func (p ADCPin) Configure() {
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}
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