LS Mini: Add a JTAG port

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Linkstation Mini


CN7 and C227
Vias under C25
  • Add a 10-pin JTAG connector at the pads labeled CN7. The pin numbering is the same as CN3 on Install_a_JTAG_Port.
  • Bridge TMS at the two pads labeled C227 on the top side, near the CPU.
  • Bridge TDO under C25 on the bottom side, near CN7.


Open On-Chip Debugger
> reset
JTAG tap: feroceon.cpu tap/device found: 0x07926041 (mfg: 0x020, part: 0x7926, ver: 0x0)
JTAG Tap/device matched
> halt
target state: halted
target halted in ARM state due to debug-request, current mode: Supervisor
cpsr: 0x800000d3 pc: 0x00f3aac0
MMU: disabled, D-Cache: disabled, I-Cache: enabled
> flash probe 0
Flash Manufacturer/Device: 0x00bf 0x00d6
flash 'cfi' found at 0xfffc0000
> dump_image currentcontents.bin 0xfffc0000 0x40000
dumped 262144 byte in 156.199112s


  • This procedure has been tested on only one unit. Someone please confirm.
  • Writing to the flash with JTAG has not been tested.
  • Bridging C228 instead of C227 activates another JTAG target with ID 0x5182 instead of 0x7926. One pin is probably JT_TMS_CPU and the other JT_TMS_CORE (from the Marvel 88F5182 datasheets). Apparently both cannot be active simultaneously.
  • See also this topic: