First post, by trebor
In an earlier post concerning Defender of the Crown, 'Fizzban' did some debugging and related the following:
"Starting at 8000:9573, the game is copying data byte for byte to 8000:0000 (probably some unpacking). It keeps the target position of the next byte to write as FAR pointer at 8000:0126.
Unfortunatly, that pointer is eventually overwritten and then points to the middle of the interrupt vector. So the remaining copying is completly messing up most of the vectors. As soon as the game try to call the next interrupt (int 0x81 to be precise), it ends in a non-code area and crashes.
No idea so far why this is happening though.."
Here's the basic summary (Non-Technical):
The crashing does not occur if the *.conf file is left at the default 'machine=vga'. The game plays in 'EGA mode'. You play through the whole game without a problem with PC Speaker sound.
When setting 'machine=tandy', places the game in 'Tandy Mode' which enables the Tandy 3-chip sound. However, the came crashes right after the message: "Insert Reel 2 - Press Any Key to Continue".
See prior post and further details here:
Defender of the Crown - EGA version
Any insights or thoughts on what can fix this?
Thanks,
Trebor