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mango_one
Mango One
=====
[Open this project in 8bitworkshop](http://8bitworkshop.com/redir.html?platform=verilog&githubURL=https%3A%2F%2Fgithub.com%2Fsehugg%2Fmango_one&file=mango1.v).
A simple 6502-based computer inspired by the Apple I, implemented in Verilog.
For the 6502 CPU, we use an [open-source model](https://github.com/Arlet/verilog-6502)
created by Arlet Ottens.
The Mango One's memory map is very similar to the Apple I:
Start | End | Description
------|----------|----------
$0000 | $0FFF | RAM
$A000 | $CFFF | Expansion ROM
$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](http://8bitworkshop.com/redir.html?platform=verilog&githubURL=https%3A%2F%2Fgithub.com%2Fsehugg%2Fmango_one&file=mango1.v) and try it out!