The error message for creating an I2S object on the rp2040 platform
in CircuitPython can be misleading when the word_select and data pins
are not sequential. This change updates the error message to provide
clearer guidance by specifying "GPIO pins" instead of just "pins".
The revised message now reads:
ValueError: Bit clock and word select must be sequential GPIO pins
Closes#8058
Signed-off-by: Sumitra Sharma <sumitraartsy@gmail.com>
This is needed so that the floppy flux reader can enable the pull up
on the index pin while using it as a pio jmp pin.
Also fixes a doc bug where the `jmp_pin` was omitted in one spot in the docs.
1. Check for correct error values from dma_claim_unused_channel.
2. Introduce a .stereo flag for simplicity.
3. Clarify PWM carrier frequency choice.
4. Start introducing quiescent audio value. Still need to ramp up/down.
5. Redo audio stop logic a bit.
6. Fix (unrelated) displayio dependency things.
There is still an interference problem between other DMA users and audio. Still debugging this.
This adds I2SOut and PDMIn support via PIO.
StateMachines can now:
* read and read while writing
* transfer in 1, 2 or 4 byte increments
* init pins based on expected defaults automatically
* be stopped and restarted
* rxfifo can be cleared and rxstalls detected (good for tracking when
the reading code isn't keeping up)
Fixes#4162
