Deep Dive w/Scott: RP2040 audio and DMA debugging #adafruit #raspberrypipico
86This week we talk audio playback with the RP2040. Ladyada drops by as well to chat about the RP2040 and CircuitPython.
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Deep Dive happens every week. Normally Fridays at 2pm Pacific but occasionally shifted to Thursday at 2pm. Typically goes for two hours or more. Questions are welcome. Next week is on Friday.
Links
Adafruit AR for pin overlay on Pico https://blog.adafruit.com/2021/02/05/display-raspberry-pi-pico-overlay-in-adafruit-ar-update-ios-raspberrypi-ar/
RP2040 die photos https://twitter.com/johndmcmaster/status/1355092011829719046
Working branch for Audio https://github.com/tannewt/circuitpython/tree/rp2040_audiopwmio
0:00 Welcome and hellos
07:47 Housekeeping
13:32 - tiny uft channel created
15:00 Scott’s FPGA fantasy: ( no credit to dcd :-) )
William D Jones Is working on adding Lattice MachXO2 support to the OS FGPA Tools https://twitter.com/cr1901/status/1356042679608606721
15:40 Is UART planned in CircuitPython for the Pico?
18:00 Ryzen discussion ( 5 seconds to build rp2040 build on ASUS ROG Crosshair VIII Hero, while rpi build took minutes )
22:24 I tried looking at sleep on the nrf, can you explain the esp32s2 code and where the calls would differ? Also, where do the nrf specific libraries live?
23:49 Sleep. Continued
27:28 NRF datasheet 5.2.1.1
32:00 NFR power on github
35:27 Circuit Python in space satellite - see adafruit blog - https://blog.adafruit.com/2021/02/02/inside-the-v-r3x-space-mission-circuitpython-is-now-in-space-circuitpython-space-maholli404/
38:40 Adafruit AR app for RP2040 and iOS
47:24 Audio on the Adafruit Feather!
51:20 review code.py for audio
52:30 foamyguy streaming tomorrow morning 10am central time
53:00 back to code.py…
53:50 Logic analyzer ( Logic 2 )
55:30 PWM output - verified that the code doesn’t work :-)
57:30 Stema Speaker for audio
1:10:30 RP2040 Datasheet for PWM
1:15:08 audio_dma.c code
1:17:33 Ladyada / mystery guest
1:20:01 Arm vs RISCV choice ( Why do you think they went with ARM and not RISCV? )
1:22:26 @arturo182 has the same RP2040 Zero sized so you both have one and wait for the chip?
1:23:30 Adding easy for people to add new boards to CP ( RP 2040 might bring the board count to 200 )
1:26:30 Audio algorithm discussion PWM / sine wave
1:28:00 Timers on RP 2040
1:31:50 Not enough pins on the “gameboy” thing
1:35:17 - Issue #4 - buffering data from the adc…
1:42:02 WM 8960 for I2S ( UDA chip discontinued )
1:44:42 - goodbye LadyAdy
1:45:00 resync / questions ….
1:48:45 X-Ray scans ( also decapped RP 2040 ) https://twitter.com/johndmcmaster/status/1355093011923750912
1:52:40 RP 2040 interpolator and divider peripherals
1:54:22 Interpolator in the Datasheet 2.3..1 SIO ( under Processor subsystem )
2:00:00 UART from PrimeCell UART (PL011)
2:01:20 back to Interpolator
2:03:05 back to conversion code in audio_dma.c
2:04:00 RP2040 desired ‘improvements’
2:05:55 pioasm complete? Missing features.
2:06:30 github rp2040_audiopwmio
2:07:29 plans for second rp2040 second core
2:10:59 wrap up ( mistakes credit to dcd :-) )
2:13:53 pet the cat
2:14:36 signs off