Copyright © 2009 Purdea Andrei
The s3e-sk, and the 7seg board
The hexadecimal timer in action  download video download image
The back of the 7seg
Waveforms in gtkwave

7seg s3e-sk extension board

I own a Xilinx Spartan 3E Starter Kit FPGA board. Something that is quite frustrating about it is that it has no 7 segment displays, and very few buttons. So i decided to build a simple extension board for it. The big Hirose connector on the side is quite hard to find, so i went with two 6-pin headers.

Obviously the 8 i/o ports provided by them could only connect a single 7(8)-segment display, but with adding a few shift registers and making the communication serial it is possible to add more. I only implemented 4 digits, but by daisy chaining more shift registers, it is possible to extend it even more very easily.


There are two pieces of code. one is written completely in verilog, and the other one is mostly schematic and a little vhdl.