ed@qtc.UUCP (Ed Lisle) (06/09/87)
How does one enable the other background colors so one can have
16 forground/16 background colors in Microsoft C ?
+------------------------------------------------------------+
| Ed Lisle | ogcvax! |
| Quantitative Technology Corporation | verdix! qtc!ed |
| Beaverton, OR (503) 626-3081 | sequent! |
+------------------------------------------------------------+smvorkoetter@watmum.UUCP (06/10/87)
In article <292@qtc.UUCP> ed@qtc.UUCP (Ed Lisle) writes: >How does one enable the other background colors so one can have >16 forground/16 background colors in Microsoft C ? I assume you are talking about the CGA on a PC or Clone. If so, then you are out of luck. There are only 8 background colours. There are 3 bits for the foreground colour, 1 bit for foreground intensity, 3 bits for the background colour, and 1 bit for blinking. If you are using a PCjr, you can diddle with the colour map to get any of 16 colours substituting for any other colour, allowing any background colour (but still only 8 background colours on the screen at once). Stefan Vorkoetter (smvorkoetter@watmum)
bryan@druhi.UUCP (06/21/87)
In article <1005@watmum.UUCP>, smvorkoetter@watmum.UUCP writes: > In article <292@qtc.UUCP> ed@qtc.UUCP (Ed Lisle) writes: > >How does one enable the other background colors so one can have > >16 forground/16 background colors in Microsoft C ? > > I assume you are talking about the CGA on a PC or Clone. If so, then > you are out of luck. There are only 8 background colours. [More > reiteration of this point deleted.] This isn't quite true. Bit 5 of the "Mode Select Register" of the 6845 CRT controller (used in the IBM CGA and many clones) selects blinking versus 16 background colors. Doing: MOV DX,03D8H OUT DX,009H on an IBM PC with CGA will cause 80x25 color text mode to be selected with 16 background colors and no blinking. In this mode, setting what is normally the "blink" bit will now intensify the background color, giving you access to the other 8 background colors. The ROM BIOS merely sets bit 5 during the power-up initializations to enable blinking instead. -- -------------------------------------------------------------------------- John T. Bryan USENET: ...!ihnp4!druhi!bryan AT&T Information Systems PHONE: (303) 538-5172 Denver, CO 80234
dalegass@dalcsug.UUCP (Dale Gass) (07/05/87)
In article <1982@druhi.ATT.COM>, bryan@druhi.ATT.COM (BryanJT) writes: > > This isn't quite true. Bit 5 of the "Mode Select Register" of the 6845 > CRT controller (used in the IBM CGA and many clones) selects blinking > versus 16 background colors. Doing: > > MOV DX,03D8H > OUT DX,009H > > on an IBM PC with CGA will cause 80x25 color text mode to be selected > with 16 background colors and no blinking. In this mode, setting what is > normally the "blink" bit will now intensify the background color, giving > you access to the other 8 background colors. The ROM BIOS merely sets Although the following doesn't work on my cga-clone, the IBM manuals say that bit 4 of register 3d9 will 'Intensify the background colors in the alpha mode'. Thus, an MOV DX,03d9h MOV AL,10 OUT DX,AL should allow the use of the other 8 background colors (but not all 16 at once). -dalegass@dalcsug.uucp gotta include more new text than old text... gotta include more new text than old text...