kerry@bcsaic.UUCP (Kerry Strand) (03/24/88)
My problem is (besides that I'm coding in BASIC) that I have some code for switching between two monitors that worked with QuickBasic 2.0, but doesn't work with 4.0. I'm not even sure why it ever worked. I have a PC clone with two monitors, a monochrome with Hercules card and a CGA card and monitor. The BASIC code below was worked out by trial and error, based on some buggy code I got from the net. Under QB 2.0, I could switch between the two monitors. The screen I was switching TO would be cleared in the process, but that was ok, because the FROM screen would be left as it was and I would redisplay what I needed on the TO screen. With QB 4.0, I get an error, Illegal Function Call, on the statement SCREEN 1,0,0,0. I can see where this would be illegal for a monochrome screen to try to use mode 1, but previously the code wouldn't work without this. Like I say, I don't know why it used to work, so I don't know how to fix it for QB 4.0 so that it will work. Does anyone know what's going on here? Why did the code work before? Is there a better way to do my monitor switching? (more ?'s) These are subroutines used with GOSUB to switch monitors. 980 REM - switch to color monitor 982 DEF SEG = 0: POKE &H410, (PEEK(&H410) AND %HCF) OR %H10 984 SCREEN 1,0,0,0 986 SCREEN 0: WIDTH 80 988 LOCATE ,,1,6,7 ' to set the cursor size 989 RETURN 990 REM - switch to monochrome monitor 992 DEF SEG = 0: POKE &H410, (PEEK(&H410) AND %HFF) OR %H30 994 SCREEN 1,0,0,0 996 SCREEN 0: WIDTH 80 998 LOCATE ,,1,12,13 ' to set the cursor size 999 RETURN Thanks for any ideas you can come up with. Kerry Strand kerry@boeing.com Advanced Technology Center, Boeing Computer Services