andrew-jacobs / w65c816sxb-forth

A Direct Threaded Forth for the WDC W65C816SXB developer board

W65C816SXB ANS Forth

This project builds a Forth environment for a WDC W65C816SXB which can be accessed via a USB serial connection to the ACIA port. (I use a cheap PL2303 module with jumper wires acquired from ebay).

The code is split into two modules namely:

• The w65c816sxb.asm file is a general purpose vector handler and UART handler (to get around hardware problems in the W65C51 ACIA chip).

• The ans-forth.asm file is implements the forth environment. This file includes device.asm to implement hardware specific words.

A number of include files are used to support the code, namely:

• The w65c816.inc file contains useful definitions and macros for the W65C816 processor.

• The w65c816sxb.inc file contains hardware definitions for the WDC W65C816SXB development board.

Current Status

The code in this repository builds a functional Forth environment that can execute standard commands and compile new words.

W65C816SXB ANS-Forth [16.04]

: STAR ( -- ) 42 EMIT ; Ok
: STARS ( n -- ) 0 DO STAR LOOP ; Ok
CR 7 STARS
*******Ok
: SQUARE ( n -- )  DUP 0 DO DUP STARS CR LOOP DROP ; Ok
CR 6 SQUARE CR
******
******
******
******
******
******

Ok

I will continue to add documentation, more words and debug.

Bugs

• The generation of new lines during command entry needs to be improved.