A simple 6502-based computer inspired by the Apple I, implemented in Verilog.
For the 6502 CPU, we use an open-source model created by Arlet Ottens.
The Mango One's memory map is very similar to the Apple I:
| Start | End | Description |
|---|---|---|
| $0000 | $0FFF | RAM |
| $D010 | $D013 | 6821 PIA (keyboard, terminal) |
| $FF00 | $FFFF | Monitor ROM, CPU vectors |
The monitor program in ROM, MangoMon, is a custom 256-byte monitor ROM with just a few commands:
| Command | Function |
|---|---|
R aaaa |
Dump memory at address $aaaa |
| Enter | Dump next 8 bytes |
W aaaa bb |
Write byte $bb at address $aaaa |
G aaaa |
Jump to address $aaaa |
You can open this project in 8bitworkshop and try it out!