SRAM Frame Buffer is now up and running!

Exciting times for the Hope Badge Computer.

Tonight, I’ve worked out most of the kinks with interfacing the new SRAM module which you can see in posts below this, to the J68 soft-core CPU.

This means that I can now write to memory locations using 68000 assembly, and display color graphics on the screen.

The current resolution is 800 x 480, which matches the LCD. I have attached a VGA LCD Monitor to the FPGA. That interface, the computing shield that you can also see a couple posts down, uses a 12-bit DAC, therefore, the current color depth is 12-bits. Which works out to be 4096 colors. I can support 16-bits on the 7.0 touchscreen, or 16-bits using a better/different DAC for VGA. This is without any other modifications.

The plan is to get to 24-bit color, but everything in due time!

Time to start practicing my 68K assembly!

About the author

keith

Amateur Electronics Design Engineer and Hacker