Posted on November 07, 2016 at 02:38
I too seem to be unable to talk to my F I just finished some new boards with a new design.
I'm using NRST, SWDIO and SWCLK to connect from the SWD header of a discovery board to the F I triple checked and confirmed that SWCLK is on pin 20 (PA14) and SWDIO on pin 19 (PA13). NRST is pulled high, even though the NRST state doesn't really matter for SWD connection. I tested that using another board. Works fine with NRST low or high.
This is what ST-Link says about the problem:
cErrLog::SetLogTraceOn
STLinkUSBDriver.dll loaded
ST-Link/V2 device detected
Target voltage detected: 2.893326
Error (0x16) after target cmd F2 30 A3 00 00 00 00 00 00 00
Error (19) while initializing ST-Link in SWD mode
ST-Link/V2 device detected
Target voltage detected: 2.896161
Error getting target IDCODE: if SWD, check SWD connection
Error (4) while initializing ST-Link in SWD mode
ST-Link/V2 device detected
Target voltage detected: 2.893326
Error getting target IDCODE: if SWD, check SWD connection
Error (4) while initializing ST-Link in SWD mode
ST-Link/V2 device detected
Target voltage detected: 2.894743
Error getting target IDCODE: if SWD, check SWD connection
Error (4) while initializing ST-Link in SWD mode
Error (0x16) after target cmd F2 3E 00 00 00 00 00 00 00 00
Error (19) in ReadMemory_32Bit (4 bytes from 0x40015800)
Error (0x12) after target cmd F2 36 04 58 01 40 00 00 00 00
W at 0x40015804: 0x00000000
Error (0x12) after target cmd F2 35 04 58 01 40 00 00 00 00
W at 0xe000edf0: 0xa05f0000
Error (0x12) after target cmd F2 35 F0 ED 00 E0 00 00 5F A0
And this is what it looks like when debugging the lines directly:
[url=https://postimg.org/image/acq3k3qw9/][img]https://spostimg.org/acq3k3qw9/screenshot.png[/img][/url]
[url=https://postimg.org/image/t6bwh3p49/][img]https://spostimg.org/t6bwh3p49/screenshot2.png[/img][/url]
Looking at the analog version of SWDIO, it seems as if the F042 pin is somewhat struggling to drive the line properly during the IDCODE request?
It's also weird that there are transitions happening in between bits.
This is a snapshot of the PCB layout with the SWD tracks highlighted:
[url=https://postimg.org/image/m6ud5k00z/][img]https://spostimg.org/m6ud5k00z/pcb.png[/img][/url]
Those pins go directly to the SWD header on the discovery board using a 10 pin ribbon.
Any idea anyone?
Thanks!
(btw: the forum is painstakingly slow and why doesn't it read html or bbcode?)
Edit: never mind. SWDIo and SWCLK were swapped ...... I'll leave this here for everyone else to learn from 🙂
#stm32f042-swd-idcode
