flutter_gpiod

Description:

flutter gpiod

📰 NEWS #

migrated to null-safety
SignalEvent's time property is no-longer that accurate, but instead two new properties, timestampNanos and timestamp are now provided which are super accurate. (This is because of changes in the kernel)
Raspberry Pi's main GPIO chip is no longer called pinctrl-bcm2835 on Pi 4's with latest kernel version. Instead its called pinctrl-bcm2711.

flutter_gpiod #
A dart package for GPIO access on linux / Android (root required) using the linux GPIO character-device interface. Tested & working on ARM32 but should work on other 32-bit and 64-bit linux platforms as well.
Getting Started #
Then, you can retrieve the list of GPIO chips attached to
your system using [FlutterGpiod.chips]. Each chip has a name,
label and a number of GPIO lines associated with it.
final chips = FlutterGpiod.instance.chips;

for (final chip in chips) {
print("chip name: ${chip.name}, chip label: ${chip.label}");

for (final line in chip.lines) {
print(" line: $line");
}
}
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Each line also has some information associated with it that can be
retrieved using [GpioLine.info].
The information can change at any time if the line is not owned/requested by you.
// Get the main Raspberry Pi GPIO chip.
// On Raspberry Pi 4 the main GPIO chip is called `pinctrl-bcm2711` and
// on older Pi's or a Pi 4 with older kernel version it's called `pinctrl-bcm2835`.
final chip = FlutterGpiod.instance.chips.singleWhere(
(chip) => chip.label == 'pinctrl-bcm2711',
orElse: () => FlutterGpiod.instance.chips.singleWhere((chip) => chip.label == 'pinctrl-bcm2835'),
);

// Get line 22 of the GPIO chip.
// This is the BCM 22 pin of the Raspberry Pi.
final line = chip.lines[22];

print("line info: ${line.info}")
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To control a line (to read or write values or to listen for edges),
you need to request it using [GpioLine.requestInput] or [GpioLine.requestOutput].
final chip = FlutterGpiod.instance.chips.singleWhere((chip) => chip.label == 'pinctrl-bcm2835');
final line = chip.lines[22];

// request it as input.
line.requestInput();
print("line value: ${line.getValue()}");
line.release();

// now we're requesting it as output.
line.requestOutput(initialValue: true);
line.setValue(false);
line.release();

// request it as input again, but this time we're also listening
// for edges; both in this case.
line.requestInput(triggers: {SignalEdge.falling, SignalEdge.rising});

print("line value: ${line.getValue()}");

// line.onEvent will not emit any events if no triggers
// are requested for the line.
// this will run forever
await for (final event in line.onEvent) {
print("got GPIO line signal event: $event");
}

line.release();
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