Flash Loader fails system boot with STM3220G-EVAL

[doug239955]

Posted on November 18, 2015 at 17:21

Hi,

I have a STM3220G-EVAL board that I am trying to flash using CN16 (USART3) and the Flash Loader Demonstrator. I have tried both v2.5.0 and v2.8.0 of the Flash Loader and get the same result; either ''Unrecognized device...'' or ''No response from the target''.I can enter the system boot mode in 1 of 3 ways:1. Set BOOT0 == 1 and hit the RESET PB;2. Hit the Key PB which initiates a PC (0x1fff0004) + MSP (0x20001000) boot jump;3. Hit the Tamper PB which initiates a write to RAM (0x2000FFF0), forces a reset, checks RAM for the written var in startup and then branches to 0x1fff0004.I have setup a script running through my serial terminal and have confirmed that I am able to send the commands specified in AN3155 (USART protocol used in the STM32 bootloader) and can confirm that I get positive responses for all messages except Erase and Extended Erase. I'm able to write and readback from RAM (0x2000FFF0) and Flash (0x0800127C) which overwrites the (const) variable defined to be written to RAM. Each approach for entering the system boot mode works with my script, but none work with the Flash Loaders. Kind of run out of ideas now so any suggestions would be appreciated.Thanks #flash-loader-demonstrator #stm3220g-eval

[Tesla DeLorean]

Posted on November 18, 2015 at 18:07

Don't know, have you got the parity setting correct in the Flash Demo?

[doug239955]

Posted on November 19, 2015 at 09:15

It's set to Odd parity and 8 data bits. I've tried various baud rates between 9600 and 115200, but mainly plumped for 19200.

[Tesla DeLorean]

Posted on November 19, 2015 at 12:49

The loader is expecting it to be EVEN, so I'd imagine some of your issues start there.

[doug239955]

Posted on November 19, 2015 at 19:10

Sorry, I was looking at my serial terminal as I was in between reinstalling v2.8.0 and it had got set to Odd. Disconcertingly it works with both even and odd parity from the terminal. The Flash Loader, which defaults to Even, unfortunately doesn't work with any.

I've scoped the Rx line up, which starts high and I see 0111111110, it then returns high. The Flash Loader starts high and I see 0111111110 again but after returning high it is quickly pulled low.

[Tesla DeLorean]

Posted on November 19, 2015 at 19:59

Unfortunately not a board I have. I've used the System Loader in a number of STM32F205 designs without issues. The auto-bauding is a one-shot deal, and sensitive. People have run into issues with USB-to-Serial dongles, on-board serial connectivity is generally more robust.

Can't say I've looked at the F2 loader code recently, but the F1 does switch into 9-bit Even Parity mode (8+1 Parity).

[doug239955]

Posted on November 20, 2015 at 09:36

OK, thanks anyway. Guess I'll be writing my own Flash Loader sooner than I'd planned