This project was originally for my own private personal use, but I am deciding to make this a repository anyway.
This is also my first time using vias on a PCB layout! Oh, this was made with KiCAD 7.0, so any earlier release will not work.
The circuit was tested with a 74HC244 IC and TJTAG 3.0.1 and 3.0.2.1 on a few machines with success barring issues with using one 74HC244; replacing it with another 74HC244 from the same set fixed the recognition issue. This is why a 74HCT244 is recommended with this circuit.
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This same circuit on a perfboard - prototype unit before the final PCB design... photos aren't as clear; my long retired LG G7 ThinQ was better for this. Also, the jumpers for switching 3V3/5V0 exist because I do not have a DPDT switch on hand.
Top view
Bottom view
