Our setup: Fedora Core 3 linux, kernel 2.6.12-1.1378_FC3. gcc version 3.4.4 20050721 (Red Hat 3.4.4-2). Dell motherboard USB (1.1)

Hooked up to Spartan-3 eval board with 6" ribbon cable. Connections:

  QuickUSB       Signal   Spartan-A2 pin (FPGA)
 J2 8            IFCLK    35 (D9)
 J2 19, 21...33  FD0-7    19..33 (B5...A13)
 J2 22           REN      22 (B7)
 J2 24           WEN      24 (B8)
 J3 4            SLRD     4 (E6)
 J3 6            SLWR     5 (D5)
 (plus GNDs)

Simple FPGA firmware which just monitors REN, WEN and sends counter values for reading. Read data checked superficially. Write data not checked (just word count). Results:

  • Reads, writes work for 128, 256, 512 bytes at a time using master mode

Other byte counts cause mysterious problems. After a failure, it seems that re-enumeration is required to restore order.

Slave mode doesnt work at all (yet). Tried loop-back:

  slwr <= not ren
  slrd <= not wen

With and without the not'. Doesn't work.

Last modified 9 years ago Last modified on Nov 8, 2013, 10:17:53 AM