FPGA: FPGA: PDP8
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FPGA: PDP8 Hans Pufal has built a PDP8 FPGA implemenation! This web page describes how to configure your B5 or B3 to run it. There are four basic steps:
  1. Configure Hardware
  2. Build software
  3. Run on the hardware
  4. Download additional programs

Configure Hardware

First, you'll need the following hardware to use this: There is an alternative: If you have the B3 from Burch, then you're still OK, because Hans originally built this for a B3 and that configuration is documented Not Yet. I had purchased the B5-X Super Value Pack, and am very happy with it. Now, we need to configure the hardware in the following manner:
  • The SRAM needs to be connected to ports A & B.
  • The switches need to be connected to port C.
  • The Peripherals Connector needs to be connected to port G. Note: This is a 5V device, so adjust the jumper accordingly.
  • And, ultimately, we'll connect the Parallel Port cable to port H. The way to do that is simple. Given that you've got the JTAG already connected right there near port H already (that's you download to the FPGA, right?), then it's a simple matter to grab another port cable (just like all the other cables used to connect the other devices to your FPGA B5 board) and connect it between port H of the B5 and J4 on the download board. At this point it's worth noting that the way you enable the Parallel Port capability is to press the button on the download board nearest the B5 (right 'below' the J4 connector). That should cause the "LOCK" LED to turn on (it's RED). When you push the other button (near J3) the "PROG" LED will turn on (it's GREEN).
That's the physical connections for the B5 board. You'll also need a VGA monitor, a VGA board, and a PS2 (or regular PC style) keyboard. The VGA will be the first thing to come to life when you download the software. And, we'll get to that in a moment.

Build Software

By now you have probably downloaded the Xilinx Web-Pack development tools for your B5. But, if you haven't, now would be a swell time to do that. I'll wait patiently while you do that. You'll need to register with Xilinx and they'll give you a download code, etc. So, go off and get yourself the proper software. Now you need to download the PDP8 source code.