In an
earlier blog post I mentioned
Enhanced 6502 BASIC by Lee Davison. This is a very powerful and extensive
version of BASIC. A version of it was ported to the
Replica 1. This was version 1.10 back in 2005. I couldn't find a port of the most recent version 2.22, so I spent an evening and got it running on the Replica 1. All that is really needed to port it is to implement the routines for character input and output. I also had to adjust the start and end memory locations. I also made a few changes so it would compile with the cc65 assembler.
 |
| Startup Screen |
You can get my port
from here. As well as source there is a prebuilt Woz monitor binary you can use that runs from RAM. BASIC resides starting at address $5000 so you have about 20K of space available for programs if you accept the default and just press
Enter when prompted for "
Memory size?".
There are some known limitations: IRQ and NMI handling is not implemented because the vectors are in the Woz monitor ROM and cannot be changed. The SAVE and LOAD commands do nothing. I haven't done much testing so there could be bugs.
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| A Small Program Running |
When I get my 16K EEPROM board running I'll try linking it in EEPROM instead of RAM and then all 32K RAM will be available for BASIC programs.
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