Arduino for STM32

Thank you again for your time helping me with this, it is appreciated. When I connect over SWD and using the ST-Link it reports: 11:57:56 : ST-LINK SN : 081601013212364D434B4E00 11:57:56 : V2J35S7 11:57:56 : Connected via SWD. 11:57:56 : SWD Frequency = 4,0 MHz. 11:57:56 : Connection mode : Connect ...

So in order to be able to use the USB on the STM32F103C8 I need to sacrifice 8kB for the bootloader and then another ~10k for the USB code so my available program space drops from 64k to ~46k or I lose 1/3 of my program space?

So I think your binary is not valid. What you can try is to disable the U(S)ART support in the menu if you do not use HardwareSerial. You can also try to use the BluePill F103CB (or C8 with 128k) targert. Several bluepill with C8 have in fact 128K. Sorry, I'm not sure what you mean by "binary ...

I am running the generic_boot20_pc13.bin boot loader if that's what you mean by "conventional". The board now enumerates a STM Serial port now (before it came up as Maple). In my simple test I found that the flash usage was the same for CDC supersede and CDC no generic. I can flash the sim...

Thanks for the explanation. It seems the next issue I am facing is the limited flash in the STM32F103C8. I ran the blink sketch with and without the CDC and I calculated that using CDC takes 10,888 Flash and 2,960 of RAM. My program without USB compiles to 50,684 and 1,496 which should leave me enou...

Yes, I have a 1.5k pull up on D+. Based on the fact that at one point I did get both the Maple COM port and the DFU device to show up in Device Manager I think that indicates that the hardware is OK. I was able to access my board over SWD so I flash the generic_boot20_pc13.bin bootloader onto the bo...

At the bottom of that page you linked in is what I'm doing. I have flashed the fastboot bootloader and the IDE was configured to use the Maple DFU bootloader which did work as it flashed my program but I don't see anything about setting the USB Support mode. However I just tried changing that to CDC...

I was/am using the serial port for debug messages. Isn't the CDC a completely different bootloader? Don't you think my current issue is a problem with the bootloader or perhaps the drivers I installed? I wouldn't expect the drivers to be an issue since I have seen both the COM port and the DFU devic...

Yes, I do have STM32 Core installed, version 1.9.0, I just checked in the Board Manager. Before this last successful program flashing the board was always coming up as a Maple COM port. Now it is showing up as an unknown device so that sounds like a driver issue in Windows, not a program problem. I ...

OK, sorry, not enough coffee yet this morning I guess. I need to pull nRST low to reset the device and I was trying to pull it high. Now when I pull nRST low the board does drop out of the Device Manager but it comes back with that unknown device. That even happens when I pull the USB cable and do a...