STM32F103C8T6 ST Bootloader Not Responding to CubeProgrammer over UART

[UEdiz]

I am trying to program an STM32F103C8T6 over USART via the System Memory Bootloader. I've already tried with PL2023 and FTDI FTR232RL based USB-TTL converters. I've tried with multiple computers and multiple tools provided by ST. Also, I tried jumping from user code to bootloader besides pulling BOOT0 to HIGH. Whatever I tried, the chip is not responding. I can see the initial 0x7F bytes via a logic analyzer on the bus and the chip is just silent. I tried with BluePill and a custom PCB which is assembled using an F103 chip that was desoldered from an original Nucleo board (the chip was an STLink obviously, and I flashed the chip using another STLink).

My main application which highly relies on USART1 works as expected. So I don't think there is an issue with the USART pins or PCBs I've used. STM32F103 is not listed in AN2026 AN2606, so is there any chance that particular model doesn't have a ROM bootloader?

[TDK]

> STM32F103 is not listed in AN2026, so is there any chance that particular model doesn't have a ROM bootloader?

You mean AN2606? I think "STM32F1 Series" means it applies to all STM32F1 chips.

 

In any case, the various STM32F1 bootloaders are in the document.

 

Are you using the pins listed in the document?

[UEdiz]

Yes, I mean AN2606. Sorry for the typo.

I am using the pins listed in the document. After a few tries, I found out there is something wrong with my USB-TTL converters or related drivers. The third USB-TTL cable worked for me and I am able to use the bootloader. I use the other USB-TTL cables for various projects and they worked just fine until now. Maybe there are more strict timing requirements with the bootloader which I do not aware of and converters struggled with them. Everything seems fine now. I was just unlucky with my equipment.