quan@sol.surv.utas.oz (Stephen Quan) (01/09/91)
I have made mode 8 from the Advanced Users Guide, and know would like to make a black and white mode similar to the top part of the screen in Elite. Basically it was 32x32(?) characters, (if the black and white part were to fill the screen). I been modifying mode 8, but still could not get anything like it. Reason of use: Each line takes 256 bytes of storage, which makes it simpler to address bytes for graphics. Stephen Quan, Uni of Tas.
vac122g@monu6.cc.monash.edu.au (Daniel Bowen) (01/11/91)
In article <quan.663387431@sol>, quan@sol.surv.utas.oz (Stephen Quan) writes: > I have made mode 8 from the Advanced Users Guide, and know would like to > make a black and white mode similar to the top part of the screen in Elite. > Basically it was 32x32(?) characters, (if the black and white part were to > fill the screen). I been modifying mode 8, but still could not get anything > like it. > > Reason of use: Each line takes 256 bytes of storage, which makes it simpler > to address bytes for graphics. Try something like this: 10MODE4 20VDU23;1,32;0;0;0;0;0;: REM MAKE SCREEN 32*8 =256 BYTES WIDE 30VDU23;2,46;0;0;0;0;0;: REM CHANGE SCREEN POSITION.. LIKE A HORIZONTAL *TV The OS of course won't expect it, so any printing using OSWRCH will be out of position. The screen will still start at &5800 and go to &7FFF, but not all of it will be visible. Hope this helps. Daniel Bowen Starving but surviving beeb owner. -- Raymond Luxury-Yacht | HAPPY NEW BEER!!!!!! | I've got an IQ of 6000. a.k.a. DANIEL BOWEN |-------------------------------| Which is the same IQ MONASH UNIVERSITY, | vac122g@vx24.cc.monash.edu.au | as 6000 P.E. teachers. MELBOURNE, AUSTRALIA |vac122g@monu6.cc.monash.edu.au | [Holly, Red Dwarf]
terros@sideways.gen.nz (Dave Sainty) (01/12/91)
quan@sol.surv.utas.oz (Stephen Quan) writes: > I have made mode 8 from the Advanced Users Guide, and know would like to > make a black and white mode similar to the top part of the screen in Elite. > Basically it was 32x32(?) characters, (if the black and white part were to > fill the screen). I been modifying mode 8, but still could not get anything > like it. > > Reason of use: Each line takes 256 bytes of storage, which makes it simpler > to address bytes for graphics. ok, this is untested, but I think I've got what you want here. register 1 is the chars displayed register. in mode 4, 1 char is 1 byte, so no problems there. just do: ?&fe00=1:?&fe01=32 to do hardware scrolling in your new mode, you will have to set the addressable latch to 8K, which is luckily possible, because it's mode 6 size. ?&fe40=12:?&fe40=5 this may be wrong, I suggest you disassemble from &c300 (a=mode) to verify this, if you can. or, someone else could post corrections. Dave.