nev@edison.GE.COM (Niles VanDenburg) (10/11/87)
Help - is there any one out there in netland that can help me with a problem I am having with programming an EGA card (Video 7 VEGA with external 25 Mhz dot clock driving an IBM Enchanced Color Display) so as to get a graphics mode 10 that uses the external dot clock to give 992 dots per line. Basically I have already got this configuration to work in alpha mode to give 124 chars/line but when I use the same techniques for modifying graphics mode 10 parameters I get a stable display screen but I am unable to get the left 1 - 2 inches of the regen buffer to display properly - what I get is 1 - 2 inches of blank screen on the left then 4 columns of "garbage" dots and then the rest of the regen buffer is properly displayed. The modifications that I am presently using for the changes to mode 10 parameters in the BIOS are as follows: db 124d,24d,14d ; columns, rows, pels/char dw 0b000h ; page length db 001h,00fh,000h,006h ; sequencer parameters db 0abh ; misc. reg db 08dh,07bh,081h,037h,07ch,02dh ; CRT controller params. db 06ch,01fh,000h,000h,000h,000h db 000h,000h,000h,000h,05eh,02bh db 05dh,03eh,00fh,05eh,00ah,0e3h db 0ffh The attribute parameters and graphics parameters are unchanged from those already present in the mode 10. Note that the VEGA has 256K memory on it so that the BIOS mode 10 for greater than 16K is used. Thanks in advance Niles VanDenburg / nev@edison.ge.com / 804-978-5780 (work) 804-973-8464 (home) / 2495 Whitney Ct., Charlottesville Va 22901