Remora - Rpi Software Stepping Using External Microcontroller via SPI

The only problem is STM32F4. Where do you get them today?

I was just looking into a PCIe to SPI bridge for the Pi Pico (RP2040) so that they may be used in an x86 PC or with an arm64 board.

Heh, I just checked with Digikey and    5,314 In Stock of the STM32F446    $8-11ea

So maybe 

cakeslob wrote:

github.com/Expatria-Technologies/Flexi-HAL

Looks like this guy is cookin something

So cool to have a board developed to use Remora

While waiting for the EC300 to arrive I've put the SKR3 back on the bench. JojoS has done some work for the SDIO driver for Mbed, which I have not been able to get working. Mbed is also not working when trying to use the standard bootloader and I've past trying to figure this out. Cakeslob has had issues with the bootloader on other boards and it appears to be something deep in the Mbed code which is affecting clock settings or something. I also saw this for the F103 which ran sloooow.

So back to STM32cubeIDE which plays nicely with the bootloader. I've managed to mount the SD card, but now trying to figure out why transfers to the card hang. JojoS seemed to have the same issue so hopefully his insights can help.

Success, SKR3 SDIO SD read and write working with DMA and cache maintenance.

Now to get DMA SPI working....

Awesome, are you doing it all on stm32cube now?

it appears to be something deep in the Mbed code

thats the maddening part. Seems to be chip specific also, considering 407 firmware works on 446, but 446 firmware doesnt work on 446

Yes, the work on the SKR3 STM32H743 is on STM32CubeIDE. Debug capability has been so handy.

I'm thinking once with SKR3 is up and running to circle back to the other boards to move them to CubeIDE also. We'd lose the single code base (unless someone knowledgeable has a good method) but at least we don't have the unknown code in play. Mbed was handy for the handy API's but with the NVEM and EC500 work we have IO and PWM sorted, would just need to rework the analogue for the thermistor inputs.

Remora, would end up like Marlin etc with board / MCU specific versions.

Thoughts?