Path: utzoo!attcan!uunet!husc6!think!bloom-beacon!mit-eddie!rutgers!att!lzaz!mtunb!dmt From: dmt@mtunb.ATT.COM (Dave Tutelman) Newsgroups: comp.sys.ibm.pc Subject: Re: US PC programmers still live in a 7-bit world! Summary: ...and INT for PC special font Message-ID: <1257@mtunb.ATT.COM> Date: 12 Jul 88 12:30:43 GMT References: <1988Jun22.223158.1366@LTH.Se> <699@omen.UUCP> <1288@odyssee.UUCP> <29@cybaswan.UUCP> Reply-To: dmt@mtunb.UUCP (Dave Tutelman) Organization: AT&T Information Systems - Lincroft, NJ Lines: 33 In article <29@cybaswan.UUCP> iiit-sh@cybaswan.UUCP (s.hosgood) writes: >Can you reprogram the character set in an IBM-PC to put in the characters you >want?? Rumour has it that INT $1F points to a table of characters with codes >$80 - $FF. It seems to be ignored on my clone-XT (monochrome adaptor fitted). Yes, but ONLY for graphics adapters (NOT the alphanumeric monochrome) in graphics mode (NOT in character mode). The table is a set of bitmaps (e.g. - eight 8-bit bytes per character for the CGA, giving an 8x8 bitmap) for displaying characters 0x80 to 0xFF. You can create any graphics you want within the constraints of: - A standard character station is the only "brush" supported. - Only 128 shapes supported. - Must be used in graphics mode (which can be slow, and is not standard for most text-based systems). Why for graphics mode only? Because the character-only display adapters have on-board ROM to define the characters. (This may be changed for some of the new adapters; I understand the NEW Hercules has downloadable fonts.) Only in the graphics mode, where the BIOS draws characters pixel-by-pixel, is the font under software/firmware control. > Steve Hosgood BSc, > Innovation Centre, University of Wales, > Swansea SA2 8PP > Phone (0792) 295213 JANET: iiit-sh@uk.ac.pyr.swan +---------------------------------------------------------------+ | Dave Tutelman | | Physical - AT&T - Lincroft, NJ | | Logical - ...ihnp4!mtuxo!mtunb!dmt | | Audible - (201) 576 2442 | +---------------------------------------------------------------+