I’m working with a Colorlight 5A-75E [1], in combination with an Altera USB Blaster [2], using this guide [3].
When I use a minimal config file, I get this result:
$ cat myopenocd.cfg
adapter driver usb_blaster
$ openocd -f ./myopenocd.cfg
Open On-Chip Debugger 0.11.0
Licensed under GNU GPL v2
For bug reports, read
openocd.org/doc/doxygen/bugs.html
Info : only one transport option; autoselect ‘jtag’
Info : Listening on port 6666 for tcl connections
Info : Listening on port 4444 for telnet connections
Info : No lowlevel driver configured, using ftdi
Info : usb blaster interface using libftdi
Info : This adapter doesn’t support configurable speed
Warn : There are no enabled taps. AUTO PROBING MIGHT NOT WORK!!
Info : JTAG tap: auto0.tap tap/device found: 0x41111043 (mfg: 0x021 (Lattice Semi.), part: 0x1111, ver: 0x4)
Warn : AUTO auto0.tap - use “jtag newtap auto0 tap -irlen 2 -expected-id 0x41111043”
Error: IR capture error at bit 2, saw 0x3fffffffffffff05 not 0x…3
Warn : Bypassing JTAG setup events due to errors
Warn : gdb services need one or more targets defined
Now I set irlen to 8, and then it works:
$ cat myopenocd.cfg
adapter driver usb_blaster
jtag newtap auto0 tap -irlen 8 -expected-id 0x41111043
$ openocd -f ./myopenocd.cfg
Open On-Chip Debugger 0.11.0
Licensed under GNU GPL v2
For bug reports, read
openocd.org/doc/doxygen/bugs.html
Info : only one transport option; autoselect ‘jtag’
Info : Listening on port 6666 for tcl connections
Info : Listening on port 4444 for telnet connections
Info : No lowlevel driver configured, using ftdi
Info : usb blaster interface using libftdi
Info : This adapter doesn’t support configurable speed
Info : JTAG tap: auto0.tap tap/device found: 0x41111043 (mfg: 0x021 (Lattice Semi.), part: 0x1111, ver: 0x4)
Warn : gdb services need one or more targets defined
Why does openocd choose 2 as default for irlen?
Where in the source of openOCD can this be changed?
[1] chubby75/5a-75e at master · q3k/chubby75 · GitHub