Hi,
I am running OpenOCD on a Fedora host. The debugger I am using is a Busblasterv2 with jtagkey layout (Using v1.3). I have connected TCK, TMS, TDI, TDO, TRST, V_TARGET, GND and RTCK wires between the debugger and my Pandaboard. My openocd.cfg file is like,
source busblaster.cfg
source [find board/ti_pandaboard.cfg]
adapter_khz 2000
Do we really need a RTCK connection ? When I remove the RTCK wire, I notice that the TDO gets struck at 1. I was assuming that the RTCK is an optional output from the ARM chip to denote the transition of TCK from 0 to 1 as it moves through the series of sampling flipflops. It looks like RTCK is necessary for the ARM even to respond to basic IR scan. What am I missing here ? I thought the ‘adapter_khz 2000’ would notify the debugger that I m not interested in RTCK.
My second question is on the warning ‘Warn : Invalid ACK 0x6 in JTAG-DP transaction’. With the RTCK wire put back in place and with no SRST connected (Pandaboard doesn’t have the SRST), I am trying to connect to the ARM cores. The JRC is successfully probed, and that makes me think that the Busblaster v2 hardware and the v.1.3 of the Amotec jtagkey bitstream are working fine. However, the GDB seem to keep polling for the target. There is a warning on invalid acknowledgement 0x6. What are the potential mistakes one could make for hitting this condition ?
Open On-Chip Debugger 0.6.0-dev-00180-g444f202 (2011-11-02-23:22)
Info : JTAG tap: omap4430.jrc tap/device found: 0x3b95c02f (mfg:
0x017, part: 0xb95c, ver: 0x3)
Info : JTAG tap: omap4430.dap enabled
Polling target failed, GDB will be halted. Polling again in 100ms
Polling target failed, GDB will be halted. Polling again in 300ms
Polling target failed, GDB will be halted. Polling again in 700ms
Info : JTAG tap: omap4430.m30_dap enabled
Info : JTAG tap: omap4430.m31_dap enabled
Warn : Invalid ACK 0x6 in JTAG-DP transaction
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
^C
Thanks,
Ram