Hi, Jack, We noticed that one of our designs gave bogus results when run on a ROACH 1 board with a serial number in the range 02XXXX, but valid results when run on a ROACH 1 board with a serial number in the ranges 03XXXX or 04XXXX.
After much head scratching, we opened up one 02xxxx, one 03xxxx, and one 04xxxx roach. The 02xxxx roach (020247) had Cypress CY7C1263V18 QDR chips, which are 2Mx18 bits. The 03xxxx roach (030144) had Cypress CY7C15632KV18 chips, which are 4Mx18. The 04xxxx roach (040122) had NEC D44647186AF5-E25 QDR chips, which are also 4Mx18. The 2Mx18 bit QDR chips of the 02xxxx roaches can only store 1M (1,048,576) 32-bit words which was too small for our design. Hope this helps, Dave On Mar 1, 2013, at 12:27 AM, Jack Hickish wrote: > Hi All, > > Is someone able to confirm that the size of the QDR chips on ROACH 1 boards > depends solely on the board version? If this is indeed the case, does anyone > know the QDR specs for the different board iterations? > > > Cheers, > Jack
