An open source flicker fixer for Amiga 500/2000
This is the first stage in the construction of a flicker fixer/scan doubler that mounts internally in an Amiga 500 or Amiga 2000.
In order to rapidly prototype the FPGA logic I designed a small adapter board that connects pins on Denise to a DE10-Lite FPGA development board via a 5V-tolerant buffer. The KiCad files for the board are available in Hardware.
After ordering, receiving and soldering the PCB I then wrote Verilog code that samples CSYNC (composite sync) and the 12-bit RGB signals, and outputs the sampled pixels to VGA. The logic handles both non-interlaced and interlaced output from the Amiga. The Quartus project is available in HDL.
The next stage is to design a stand-alone board that contains an FPGA chip and an SDRAM chip.