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This tutorial follows a series from 'sprites mods'  to attempt to reverse engineer a hard drive controller board
JTAG Hookup Process
The first step is to hook up wires to the JTAG pins of the hard drive controller board in question.
Fortuitously, the HDD board I have appears to have the same pinout as the one on Sprites Mods for the JTAG pins. This involved a fair bit of fine tip soldering to small pads and attempting to follow traces on a dense PCB. Pictures below
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Once the pins were soldered (GND, TDI, TMS, CLK IN, and TDO), the ARM JTAG programmer had to get hooked up to the soldered wires.
The pinout of the JTAG programmer is oriented such that the power input on the bottom.