Well so far not much has been done except for a lot of reading, jotting down notes, etc.
I did find a free direct x component for Delphi last night and managed to get that installed.
I then created a new test project to test a few ideas.
The first thing I did was to create a direct draw surface on the form. From there, I added in code to switch between the window and full screen. As I test, I wrote out "Delphipede" on the surface. That seemed to work well enough.
For the next part, I created a new unit in order to begin the 6502 emulator. I have a very good idea how this will work, it's just a matter of doing all the tedious typing. To start with, I just wrote part of the init and reset procedures (enough to where I could test the first instruction $4C anyway ). I then wrote a rom load routine and and processed that first description. At this point I didn't actually perform the instruction, but rather just looked up the cycle count, instruction and address mode for the opcode I found and printed it on the screen.
So what remains for me to investigate?
1. How, when I need to refresh the screen, the directdraw surface interacts with the video ram. I was hoping I could just split the directdraw surface into a grid (240x256) and then "write" out the data from the video array as needed. I'll need to read more about how direct x works.
2. The pokey chip...though I may save this for the very very end.
3. Something else I was thinking about when I started typing this....but then forgot as it took me almost 30 minutes to type this (happens when you keep getting interrupted at work ).
ArcadeGamenut
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