Inspired by this thread from ubik and combined with my archeology excavations in the C65 ROM I made a new patch "AI" for the 911001.bin
I have added a new BASIC 10 command SVIC (for set VIC).
SVIC 3 sets the VIC-III mode (with writing $A5 and $96 in KEY register $D02F)
SVIC 4 sets the VIC-IV mode (with writing $47 and $53 in KEY register $D02F)
Every other parameter between 0 and 255 will be ignored.
Numbers below 0 and above 255 causes an "?ILLEGAL QUANTITY ERROR".
Using SVIC 4 on the C65 (xc64 emulator) will be automatically ignored from the command routine, so there will be no crash because init the VIC-IV on C65.
You can use as parameter:
numbers: e.g. SVIC 3, SVIC 4, ...
formulas: e.g. SVIC (5-2), SVIC (2*2), ...
variables: e.g. IV=4: SVIC IV, ...
In the patch "AI" there are included all changes from patch "AH", so there is only one patch needed.
Because I was asked about the original english characterset in the patched ROM , I made two versions of the patch "AI":
911001_ai_ger.bin (with German umlauts as described here)
911001_ai_us.bin (with the original chars from the 911001 ROM)
For patching process see additionally the description in this post.
bspatch 911001.bin 911001_ai_ger.bin patch_ai_ger.bin for the "ger" version with umlauts.
or
bspatch 911001.bin 911001_ai_us.bin patch_ai_us.bin for the "us" version without umlauts.
Rename the build patch rom to MEGA65.ROM for the use on MEGA65 / Nexys board.