da81784ee9
I didn't add this method in the initial PR. Also, I found that a few of my assumptions were incorrect. I've changed the code that configures the pin to make input (floating and pullup) actually work. These chips really are quite different from all the older AVRs.
62 строки
1,5 КиБ
Go
62 строки
1,5 КиБ
Go
//go:build avrtiny
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package machine
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import (
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"device/avr"
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"runtime/volatile"
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"unsafe"
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)
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const deviceName = avr.DEVICE
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const (
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PinInput PinMode = iota
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PinInputPullup
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PinOutput
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)
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// Configure sets the pin to input or output.
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func (p Pin) Configure(config PinConfig) {
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port, mask := p.getPortMask()
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if config.Mode == PinOutput {
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// set output bit
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port.DIRSET.Set(mask)
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// Note: the output state (high or low) is as it was before.
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} else {
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// Configure the pin as an input.
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// First set up the configuration that will be used when it is an input.
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pinctrl := uint8(0)
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if config.Mode == PinInputPullup {
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pinctrl |= avr.PORT_PIN0CTRL_PULLUPEN
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}
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// Find the PINxCTRL register for this pin.
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ctrlAddress := (*volatile.Register8)(unsafe.Add(unsafe.Pointer(&port.PIN0CTRL), p%8))
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ctrlAddress.Set(pinctrl)
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// Configure the pin as input (if it wasn't an input pin before).
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port.DIRCLR.Set(mask)
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}
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}
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// Get returns the current value of a GPIO pin when the pin is configured as an
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// input or as an output.
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func (p Pin) Get() bool {
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port, mask := p.getPortMask()
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// As noted above, the PINx register is always two registers below the PORTx
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// register, so we can find it simply by subtracting two from the PORTx
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// register address.
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return (port.IN.Get() & mask) > 0
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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 Pin) Set(high bool) {
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port, mask := p.getPortMask()
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if high {
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port.OUTSET.Set(mask)
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} else {
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port.OUTCLR.Set(mask)
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}
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}
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