How do I make readback work?
To verify that you have correctly working hardware run: PamTest readback. If PamTest works but you can’t readback your bitstream, look more closely at the way you created it. Firstly you must set the appropriate makebits options to enable the internal readback circuit. The relevant makebits options are: • ReadCapture:Enable • ReadAbort:Enable • ReadClk:Cclk You’ll find these (plus other required options) in any of the Makefiles in the */design/src directories of the sample designs. Secondly look for problems in the netlist itself. How do you generate your netlist? If it is not made using PamDC then your problem is probably that you have not wired-up readback. In the Xilinx 4000 series the readback facility is an *internal* circuit element that the user must connect in a user determined way. To be consistent with the way the Pamette PCB is wired you must connect RDBK.TRIG to MD0 and RDBK.DATA to MD1, RDBK.RIP may be left unconnected. An xnf fragment pulled from the Pamette sram example
