I have some HUB75 boards where the JTAG pins are covered with solder mask or only available by scratching solder mask from non-descript traces. These boards ar

I have some HUB75 boards where the JTAG pins are covered with solder mask or only available by scratching solder mask from non-descript traces. These boards are programmed in production with SPI pins or assembled with preprogrammed PROMs.