class PIO – advanced PIO usage¶
The PIO class gives access to an instance of the RP2040’s PIO
(programmable I/O) interface.
The preferred way to interact with PIO is using rp2.StateMachine, the
PIO class is for advanced use.
For assembling PIO programs, see rp2.asm_pio().
Constructors¶
- class rp2.PIO(id)¶
Gets the PIO instance numbered id. The RP2040 has two PIO instances, numbered 0 and 1.
Raises a
ValueErrorif any other argument is provided.
Methods¶
- PIO.gpio_base([base])¶
Query and optionally set the current GPIO base for this PIO instance.
If an argument is given then it must be a pin (or integer corresponding to a pin number), restricted to either GPIO0 or GPIO16. The GPIO base will then be set to that pin. Setting the GPIO base must be done before any programs are added or state machines created.
Returns the current GPIO base pin.
- PIO.add_program(program)¶
Add the program to the instruction memory of this PIO instance.
The amount of memory available for programs on each PIO instance is limited. If there isn’t enough space left in the PIO’s program memory this method will raise
OSError(ENOMEM).
- PIO.remove_program([program])¶
Remove program from the instruction memory of this PIO instance.
If no program is provided, it removes all programs.
It is not an error to remove a program which has already been removed.
- PIO.state_machine(id[, program, ...])¶
Gets the state machine numbered id. On the RP2040, each PIO instance has four state machines, numbered 0 to 3.
Optionally initialize it with a program: see
StateMachine.init.>>> rp2.PIO(1).state_machine(3) StateMachine(7)
- PIO.irq(handler=None, trigger=IRQ_SM0 | IRQ_SM1 | IRQ_SM2 | IRQ_SM3, hard=False)¶
Returns the IRQ object for this PIO instance.
MicroPython only uses IRQ 0 on each PIO instance. IRQ 1 is not available.
Optionally configure it.
Constants¶
- PIO.IN_LOW¶
- PIO.IN_HIGH¶
- PIO.OUT_LOW¶
- PIO.OUT_HIGH¶
These constants are used for the out_init, set_init, and sideset_init arguments to
asm_pio.
- PIO.SHIFT_LEFT¶
- PIO.SHIFT_RIGHT¶
These constants are used for the in_shiftdir and out_shiftdir arguments to
asm_pioorStateMachine.init.