Papilio One 250K board -> 500K modification

[mastadle]

Hello, we have been using the Papilio One 500K for around 8 years now as the control board for a mixed-signal PID controller PCB that we use within our research group. Unfortunately we've realised that it's no longer being built, and stocks seem to be low or zero across the web stores we've looked at.

One option we wanted to try was simply buying existing Papilio One 250K boards, of which there are still a fair amount available, and replacing the FPGA ourselves (we could probably also port our bitstream to the 250K but this would take more of people's time). It's not a project that we wanted to spend much time/effort on, since we were going to update the design to the Papilio Pro or better in the medium term anyway.

This was just planned as a stopgap.

Having replaced the FPGA on two 250K boards, we can program the FPGA itself without any problems using the Papilio Loader. However when we try to program the SPI flash, we get the following error:

 

 

JTAG chainpos: 0 Device IDCODE = 0x41c22093    Desc: XC3S500E Using devlist.txt JTAG chainpos: 0 Device IDCODE = 0x41c22093    Desc: XC3S500E Using devlist.txtUploading "C:\scratch\Downloads\Papilio-Loader-V2.8\papilio-loader\programmer\bscan_spi_xc3s500e.bit".

Done.

Programming time 200.4 msProgramming External Flash Memory with "C:\scratch\Downloads\Papilio-Loader-V2.8\papilio-loader\evil_fw_2015_06_02_v1.bit".

Uknown Flash Manufacturer (0x00)

Error: SPI Status Register [0x00] mismatch (Wrong device or device not ready)..

Error occured.

USB transactions: Write 67 read 9 retries 0 JTAG chainpos: 0 Device IDCODE = 0x41c22093    Desc: XC3S500E Using devlist.txtISC_Done       = 1 ISC_Enabled    = 0 House Cleaning = 1 DONE           = 1

 

It seems like the SPI chip or the communication link is faulty, but we're not sure why. Has anyone ever seen this issue with the SPI before?

Any feedback/tips would be appreciated, or other ideas on potentially sourcing some Papilio One 500K boards. (We prefer the version without headers, since that's what we need for our PCB.)

 

Thanks for your help!

[mastadle]

After checking/redoing the solder joints on the FPGA chip, the Papilio One could be flashed without any further problems.
It seems that this has fixed the problem.