Re: FPGA Implementations
Posted: Sat Jul 01, 2017 1:51 pm
About two years ago I tried to get a floppy emulator project for the Challenger 1P started. The goal was to simulate a 610 board attached to the C1P's expansion connector. I used a Papilio Duo board with 512 kB SRAM.
I started with zero knowledge of VHDL, and it was a lot of fun to learn VHDL, but at the end of the day it was too complex for me. As a first step I wanted to simulate a memory chip attached to 6502 bus, so I could write values to the FPGA's RAM from the C1P and read them back in to verify. I had to give up when I had an implementation for this that apparently worked in the FPGA simulator, but not when I tried to run it on the real hardware. I did not have enough know-how and tools to debug what was going wrong in reality...
Having said that, I would still be very interested to participate in any FPGA project that attempts to simulate the floppy controller and disks attached to the C1P. If anyone wants to work in that direction, I would love to hear about it.
Stephan
I started with zero knowledge of VHDL, and it was a lot of fun to learn VHDL, but at the end of the day it was too complex for me. As a first step I wanted to simulate a memory chip attached to 6502 bus, so I could write values to the FPGA's RAM from the C1P and read them back in to verify. I had to give up when I had an implementation for this that apparently worked in the FPGA simulator, but not when I tried to run it on the real hardware. I did not have enough know-how and tools to debug what was going wrong in reality...
Having said that, I would still be very interested to participate in any FPGA project that attempts to simulate the floppy controller and disks attached to the C1P. If anyone wants to work in that direction, I would love to hear about it.
Stephan