STM32G474xx on NUCLEO-G474RE

C programming, build, interpreter/VM.
Target audience: MicroPython Developers.
User avatar
RealSparky
Posts: 17
Joined: Tue Sep 29, 2020 4:38 pm
Location: Carlsbad, California USA

Re: STM32G474xx on NUCLEO-G474RE

Post by RealSparky » Fri Apr 02, 2021 5:33 pm

RE: uasyncio is a BEAUTIFUL thing
Just update the Google share drive folder with an updated version for the G474.
https://drive.google.com/drive/folders/ ... sp=sharing
This version increased the storage FS to 96K, has SPI3 dma working, asyncio integrated, LPUART REPL and Thonny can now load scripts to the FS /flash. The PowerMonitor_EMCS16.py is an example running on my custom HW reading ADCs and CORE TEMP.
Now I just need to figure out how to do a pull request to get things integrated into the AEMICs github release.

RealSparky, the hardware guy

User avatar
RealSparky
Posts: 17
Joined: Tue Sep 29, 2020 4:38 pm
Location: Carlsbad, California USA

Re: STM32G474xx on NUCLEO-G474RE

Post by RealSparky » Sat Apr 10, 2021 1:34 am

VCP update with STLINKV3-mini:

On Mar 29 I was having an issue with the VCP on my custom PCBA. I said, 'BTW, there is a small glitch, to use the VCP at the moment. You need to start the debugger to initialized the STLINK-V3MODS before the VCP works." On my board the PB8-BOOT0 pin is used for FDCAN_RX, which is a high level during boot. This was activating bootloader mode which hung the MicroPython boot until I started the debugger. Since I have no intention of using the bootloader it was easy to fix by unchecking the nSWBOOT0 check box in the OPtion Bytes field. In the STM32 ST-LINK Utility select Target > Options byte and uncheck nSWBOOT0 and check nBOOT0, this combination always uses Main Flash memory to boot regardless of the PB8-BOOT0 pin level. Now VCP works on every time.

If VCP does not work, you should use loopback testing by connecting tx to rx and see if characters echo back using a terminal program. This was the clue for me that I had to look for another reason why REPL prompt did not show up until the debugger was started. My custom PCBA is using LPUART1 on PC0 and PC1 for the VCP link via the STLINKV3-mini.

RealSparky, the hardware guy.

Post Reply