903 VGA clock
903 : VGA clock
- Author: Matt Venn
- Description: Shows the time on a VGA screen
- GitHub repository
- Clock: 31500000 Hz
How it works
Races the beam! Font is pre generated and loaded into registers. 6 bit colour keeps register count low.
Every minute the colours cycle.
How to test
Hook up a VGA monitor to the outputs and provide a clock at 31.5 MHz.
Adjust time with the inputs[2:0], and choose the type of VGA PMOD with the input[3].
External hardware
VGA PMOD - you can use one of these VGA PMODs:
- https://github.com/mole99/tiny-vga
- https://github.com/TinyTapeout/tt-vga-clock-pmod
Set input[3] low to use tiny-vga and high to use vga-clock
IO
| # | Input | Output | Bidirectional |
|---|---|---|---|
| 0 | adjust hours | hsync / R1 | |
| 1 | adjust minutes | vsync / G1 | |
| 2 | adjust seconds | B0 / B1 | |
| 3 | PMOD type select | B1 / VS | |
| 4 | G0 / R0 | ||
| 5 | G1 / G0 | ||
| 6 | R0 / B0 | ||
| 7 | R1 / HS |