Testing results of PXL RDO board JTAG daisy chain

Initial design

PCFiberUSB

FiberUSB

DigilentUSB - JTAG

RDOboard

Schematic for Digilent USB-JTAG module PCB

Schematic for the PXL RDO Board JTAG daisy-chain cable

Initial testing with Digilent board:• This is the first opportunity to test the full compliment of 10 RDO boards.• Initial tests with the Digilent JTAG board to individual RDO boards have been and continue

to be successful.• Tested at different JTAG frequencies from default (6MHz) to lowest using ISE Impact 14.5• Tested for 4, 6, 8, 10 boards (using board bypass switches on the JTAG cable)• All tests failed – errors were

• Wrong number of devices found• Devices not recognized• Only some devices recognized

DigilentUSB-JTAG

board

PXL JTAGDaisy-chain

cable

Since the Digilent module based design did not work for multiple boards, we tried the standard Xilinx programmer.

• All RDO boards correctly recognized.• Configuration of individual boards successful in positions 5 and 10.• Flash configuration not tested.

XilinxUSB-JTAG

programmer

Successful 10 RDO board JTAG daisy-chain using Xilinx USB programming module and PXL JTAG chain cable.