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Production Timecard: bad termination on FPGA JTAG with USB

Open wisxxx opened this issue 2 years ago • 2 comments

Ref. schematic R4006-G0001-03-SC-REV02.pdf

If using the USB interface (FT432, sht. 24), the FPGA JTAG signals are double-terminated by resistors shown at sht. 24, zone B11:

image

and sht. 10, zone J4.

image

by way of the mux'ing shown on sht. 24 "JTAG/SPI_MASTER_SEL".

wisxxx avatar Mar 01 '23 00:03 wisxxx

@julianstj1 did we address this?

ahmadexp avatar Aug 09 '23 06:08 ahmadexp

This is on the production card, and the USB interface worked when we tested it, but definitely this double termination should not be there. If we ever have another BOM change on there, I will add this on, thanks for the great catch!

julianstj1 avatar Aug 09 '23 15:08 julianstj1