spartan-3e spi problems

Hi, I am having trouble configuring a xc3s250e from a st m25pe20 spi flash rom. Originally init would not go low and the chip was constantly looping through the config. I inserted a 256 0xFF's at the beginning of the mcs file and now init goes low, but done does not go high. Is there some number of 0's or 1's that need to be appended to the image. I am using xilinx ise 9.1. I generated the mcs file using impact and selected the generic SPI options. I have tried bit-swapping the file. Init only goes low one way. The last line of my prom image is:

:1094F00020000000200000002000000020000000EC

I have heard of a postamble that should be 0x7F, this file doesn't have one though.

Thanks,

Jon Pry

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jonpry
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init going low during means ERROR init not going low, done not asserting means that configuration not even started

init is low for short time after power-on, if it doesnt go high means FPGA is really not in working condition (INIT=1 means its ready for conf)

Antti

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Antti

Init pulses high. I can see that the fpga has downloaded the configuration and stops downloading it presumably when the correct number of bytes have been transferred. I'm pretty sure it is in the "ERROR" condition. I don't know why though.

Reply to
jonpry

connect JTAG cable at least temporarly and read back the status register, it should hold the error bits hopefully

init low error is either CRC or wrong device ID

Antti

Reply to
Antti

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