[sdiy] STM32 (or other) audio DSP learning recommendations

[Martin Klang]

The HAL and Cube software in general has really improved. I quite like 
it now and use it all the time. CubeMX is great for making pin 
assignments and generating set-up code, and the library is a massive 
time saver - when it works. I'd echo all of Scott's points about 
checking and potentially replacing performance critical functions.

But some of the H7 library code is completely untested and not fit for 
dogfood. One of my recent complaints (don't use any HAL_I2S functions!)

https://community.st.com/message/204150-re-stm32h7-i2s-hal-bugs


Martin


On 05/07/18 16:16, Eric Brombaugh wrote:
> On 07/05/2018 07:33 AM, Martin Klang wrote:
>>
>> The H7 is fun. It's a shame the HAL is so terrible. I know, it's 
>> better to roll your own, but it's a complex device and just reading 
>> the reference manual is a job in itself!
>
> HAL isn't -awful- if you use it carefully. I tend to use it just for 
> initial setup and then do direct register access for the realtime 
> control. HAL provides a nice complement of lightweight inline macros 
> for most bitbanging you might need to do so it still ends up looking 
> fairly coherent even when you're bypassing most of the heavy functions.
>
>>  From my experiments the F7 only gives a moderate performance boost, 
>> while consuming almost twice as much power. Not ideal.
>
> For the applications I do the F7 running full-bore is about 2-3x 
> faster than an F4 - mostly due to the caching, but you're right that 
> it's power-hungry. In some applications I actually dial the clock 
> frequency back a fair bit until my application just barely meets its 
> schedule deadlines just to save the milliamps. There's another penalty 
> to pay - the cache can do strange and hard to debug things. Be aware 
> of it, especially when you're working with DMA.
>
> Eric
>
>
>