I'm trying to use impact 14.6 to program eFuses of a Spartan6 LX100 FPGA.
In my JTAG chain I have six devices,
TDI-> FPGA -> IMX253 -> STV0903 -> STV0903 -> STV0903 -> STV0903 -> TDO
I started trying to work with the impagt gui, however in the end I will have to use a batch script.
The chain works, I can successfully execute chain Initialization, ID code test and chain integrity test.
Now I'm trying to read the eFuse Control Register, no luck, it gives all ones, telling me reading register is disabled (the register has never been programmed).
The same reading DNA, still all ones so far.
Reading FPGA status gives all zeroes, Device Signature / User code gives ffffffff.
Thinking about possible problems in the JTAG chain, I connected to the chain only the FPGA,
thus eliminating from the circuit all other ICs, bypassing also all PCB traces, so for sure we will have no problems
of delay, signal integrity, etc.
However also with FPGA being connected directly I have almost the same behaviour, except for reading
the eFuse control register, now it gives all zeros (correct).
But again DNA doesn't works, and I need to have the whole system working with complete JTAG chain.
What should I do?
It is VERY important to solve the problem quicky, as we would go in production sooner, and I already post some question on thsi forum months ago, no one answer ....
Where are the Xilinx Impact experts?