Michau

6509 processor emulation bugs

Here is a 610 Hungarian character set that I downloaded from Zimmers. It has something in the upper 4 kB. Generally, a standard (non-nationalized) characters ROM for 610/710 is 8 kB in size and has FF's in the upper 4 kB. Nationalized and/or special character sets will have the upper 4 kB populated with another character set. So I think for starters, you should expand your "chargen.600" and "chargen.700" to 8 kB by padding with FF, because that's what in the real machine. The code that loads 4 kB...

Yes, I presume this is some kind of DIN character set switch. WRT the questions: Yes, the character set should change immediately on the whole screen, similarly to what happens when you press C= + Shift on the C64. The font ROM I sent you is the PC emulator font; you can see the difference for example in the yhe <- (left arrow character) - in the alternate font it should turn to _ (underscore). Reverse mode and alternate charset are done by setting high address lines in the CRTC. From the schematic...

Sure, here is my ROM.

CRTC emulation is incomplete

Great, this workaround works well. I suppose I can free the sectors again after all files are placed using the B-D command.

Substituting the 8088.prg file with another file (for example, writing two copies of 6509.prg under different names) will give the same error, as long as the third file is more than 1 sector long. If you do the same test with D82, you will notice that (38,5) points to (38,12) not to (38,11). It seems that the sectors for this file in D80 image are improperly interleaved, with a value that is off by 1.

Writing PRG files to D80 images causes data corruption