| 14 May 2022 |
 ithinuel | * regarding I2S, I don't see an I2S peripheral block so you'd have to use the PIO to do that for you.
It should be fairly simple ™ to implement. | 19:25:39 |
| ithinuel | * regarding I2S, I don't see an I2S peripheral block so you'd have to use the PIO to do that for you.
It should be _fairly simple_™ to implement. | 19:25:43 |
| ithinuel | * regarding I2S, I don't see an I2S peripheral block so you'd have to use the PIO to do that for you.
It should be fairly simple™ to implement. | 19:25:56 |
 yruama_lairba | i guess it's not possible to reuse this system to add some ram? | 19:26:00 |
| ithinuel | Not as for as I know. but the device has 264KiB of RAM so it should be way enough for the usecase of the chip.
Do you need a lot more? | 19:28:21 |
| yruama_lairba | ithinuel: i far to reach the point where more ram are needed, but yes, for some audio DSP effect i need a lot of ram | 19:30:45 |
| ithinuel | oh, I never played a lot with audio/dsp so I don't know how much compute power you need for that but the RP2040 is a dual core cortex-m0. It doesn't have an FPU nor the fancy DSP instructions a cortex-m4 may have. | 19:34:11 |
| yruama_lairba | for this reason, i'm also interested by trying to bare metal on PI Zero | 19:34:17 |
| ithinuel | ( in the SDK I2S is achieved via PIO: https://github.com/raspberrypi/pico-extras/blob/b5887f6baaabb18b6e135da9115bc32402026af0/src/rp2_common/pico_audio_i2s/audio_i2s.c ) | 19:34:37 |
| ithinuel | * ( in the SDK I2S is achieved via PIO: https://github.com/raspberrypi/pico-extras/blob/b5887f6baaabb18b6e135da9115bc32402026af0/src/rp2_common/pico_audio_i2s/audio_i2s.pio ) | 19:36:33 |
| yruama_lairba | i miss understood float support of the PI pico, it's software float | 19:37:58 |
| ithinuel | there's some support in hardware, but I don't know to what extend does | 19:38:43 |
| ithinuel | https://datasheets.raspberrypi.com/pico/raspberry-pi-pico-c-sdk.pdf#section_floating_point | 19:40:36 |
| yruama_lairba | i just understand there is some float library inside the rom | 19:42:40 |
| ithinuel | that's what I understand too. It seems very well optimised but software nonetheless. | 19:44:16 |
| yruama_lairba | anyway, i'm just curious, i don't really plan to buy one soon. I may even try "bare metal" PI zero first, but it's difficult to find one at official price, many website don't have it in stock | 19:54:43 |
| ithinuel | I guess It depends of where you're based but https://shop.pimoroni.com/products/raspberry-pi-pico seems to have them in stock as well as a variety of extension (even one for audio: https://shop.pimoroni.com/products/pico-audio-pack?variant=32369490853971 ) | 19:58:15 |
| yruama_lairba | ithinuel: i was talking about pi zero | 20:00:30 |
| ithinuel | Oh for the stock, sorry 🙂 | 20:02:02 |
| yruama_lairba | and the audio pack deosn't fits my particular needs | 20:03:54 |
| yruama_lairba | for audio i have needs particular enougth to require custom design :p. i need very Hi Z input in addition to headphone out | 20:08:02 |
| yruama_lairba | i already did a design for stm32 and it costed me around 30€ and some soldering. | 20:10:15 |
| yruama_lairba | *for nucleo | 20:10:55 |
 9names | It's often been hard to buy a pi zero, but the global chip shortage has made it near impossible.
pi zero 2 W is a better choice for audio DSP, but is a bit more expensive and still difficult to obtain.
I recommend using https://rpilocator.com/ and being very patient. | 23:34:42 |
| 9names | That said - you should be able to get decent DSP perf out of a high frequency cortex-m7 device like an stm32h7 nucleo or teensy 4.1 | 23:36:35 |
| 15 May 2022 |
| yruama_lairba | 9names: at the moment, i do with thing i have (nucleof411). i may found more issue than just not enought memory for some effects | 00:47:10 |
| yruama_lairba | i may even stop my project because not having enouth time | 00:48:45 |
| yruama_lairba | i'm currently doing I2s hal for stm32f4, and it takes me a lot of time | 00:51:08 |
|  Mimir joined the room. | 02:14:42 |
| 9names | Yeah. Everything always takes longer than you want it to, especially when doing it in your spare time. | 02:53:50 |
