latest SVNs :
0.74 :
Identical confs, default except for machine type.
http://nerdlypleasures.blogspot.com/ - Nerdly Pleasures - My Retro Gaming, Computing & Tech Blog
The issue seems to be related to revision 3735, specifically the vga_memory.cpp change. Reverting the change causes the text to display normally in the PCjr/Tandy KQ1 booter with machine=pcjr, but also brings back the glitched lines in the ScubaVenture cart. 😒
I noticed that earlier with Troll's Tale (pcjr) too but forgot about it.
INT10_PutPixel needs an update. Would be interesting how the PCjr BIOS blits characters in the 320x200x16color mode. I'm quite sure it has to change port 0x3DF.
1+1=10
It doesn't read at 0x3DF but uses the copy in the BDA instead.
The problem is that the PCJr only provides a 16k memory window at the 0xB800 segment. The video mode used here has 32k however, so the accesses go to the wrong place. The solution (the PCJr BIOS also uses that) is to write to the actual memory page, not the window at 0xB800 (remember the PCJr has no dedicated video memory).
Attaching the patch.
Things to test:
- window scrolling and text output in the 640x200x4color mode PCJr
- are other video functions affected? Putpixel and thus WriteChar, and ScrollWindow are addressed by the patch.
1+1=10
Committed in r3789.
1+1=10
