Hi,
I have a custom board base on the stm32f407. I use the jtag for programming the flash. The chain is jtag -> ftdi4232 -> openocd. Till now, to program the flash I used to put the boot0 input to vcc, push the reset and then, via an openocd script I was able to reflash my code. Suddenly, all my platforms (3 same pcbs) have stopped to respond to the open ocd. I really don’t know why (may be because my kernel in the idle process uses the wfi instruction? Or maybe because I reprogram some jtag pin to other functionality?). Whit openocd I got always the same message (here is the full screen shot):
cm103lmcsemlocal:Binary alf$ openocd -f jtag_FTDI.cfg
Open On-Chip Debugger 0.7.0-dev-00079-g08ddb19-dirty (2012-12-26-21:22)
Licensed under GNU GPL v2
For bug reports, read
http://openocd.sourceforge.net/doc/doxygen/bugs.html
Info : only one transport option; autoselect 'jtag'
adapter speed: 1000 kHz
adapter_nsrst_delay: 100
jtag_ntrst_delay: 100
cortex_m3 reset_config sysresetreq
Info : device: 7 "4232H"
Info : deviceID: 67330065
Info : SerialNumber: FTVYM555B
Info : Description: uKOS - Kernel B
Info : max TCK change to: 30000 kHz
Info : clock speed 1000 kHz
Error: JTAG scan chain interrogation failed: all ones
Error: Check JTAG interface, timings, target power, etc.
Error: Trying to use configured scan chain anyway...
Error: stm32f4x.cpu: IR capture error; saw 0x0f not 0x01
Warn : Bypassing JTAG setup events due to errors
Warn : Invalid ACK 0x7 in JTAG-DP transaction
Polling target failed, GDB will be halted. Polling again in 100ms
Polling target failed, GDB will be halted. Polling again in 300ms
requesting target halt and executing a soft reset
Error: Target not examined yet
Polling target failed, GDB will be halted. Polling again in 700ms
Polling target failed, GDB will be halted. Polling again in 1500ms
Polling target failed, GDB will be halted. Polling again in 3100ms
Polling target failed, GDB will be halted. Polling again in 6300ms
Polling target failed, GDB will be halted. Polling again in 6300ms
...
...
Any ideas how I can recover the jtag connection? The only freedom I have is that I can play with boot0 state and I can download and execute a code via an additional uart. Do I have to reconfigure some special register?
Thank you for your advise,
Regards, max.