The JTAGULATOR () can find the main 4 pins of JTAG. But in order to access things meaningfully with Open OCD, it seems like usually you have to have TRST and SRST connected as well. Does anyone have any advice on generically finding these pins? Especially when no pinout is available, or you're dealing with a BGA chip?
Right now I'm trying to perform a data recovery on a Samsung SSD, with a S4LN021X01-8030 microcontroller. I'm going about things mostly like is described here:
http://fmad.io/blog-ssd-bricked-restore.html However, I can't get it to halt even when I try all permutations of TRST/SRST on the leftover pins. The debug port looks basically the same as is shown here:
viewtopic.php?f=10&t=30695, but with one less pin - so 1 pin ground, 4 pins TDO/TDI/TCK/TMS, and 2 pins unknown, but neither of which help to halt when connected to TRST/SRST on my Bus Blaster jtag.
Thoughts from the hardware experts?