707 VGA clock
707 : VGA clock
- Author: Matt Venn
- Description: Shows the time on a VGA screen
- GitHub repository
- GDS submitted
- HDL project
- Extra docs
- Clock: 31500000 Hz
- External hardware: R2R dac for the VGA signals
How it works
Races the beam! Font is pre generated and loaded into registers. 6 bit colour keeps register count low.
How to test
Hook up a VGA monitor to the outputs and provide a clock at 31.5 MHz. Connect the 6 bit colour output up with resistors to make a R2R DAC. See the circuit here: https://github.com/mattvenn/6bit-pmod-vga
IO
| # | Input | Output | Bidirectional |
|---|---|---|---|
| 0 | clock | hsync | none |
| 1 | reset | vsync | none |
| 2 | adjust hours | r0 | none |
| 3 | adjust minutes | r1 | none |
| 4 | adjust seconds | g0 | none |
| 5 | none | g1 | none |
| 6 | none | b0 | none |
| 7 | none | b1 | none |