旼컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� � Introduction to Programming the SVGA Cards � 읕컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� 旼컴컴컴컴컴컫컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� � Disclaimer � 읕컴컴컴컴컴켸 I assume no responsibility whatsoever for any effect that this file, the information contained therein or the use thereof has on you, your sanity, computer, spouse, children, pets or anything else related to you or your existance. No warranty is provided nor implied with this information. 旼컴컴컴컴컴컴컴컴컴컴컴쩡컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� � SVGA Section Overview � 읕컴컴컴컴컴컴컴컴컴컴컴� The vast majority of the information presented in the PC-GPE was obtained from the book "Programmer's Guide to the EGA and VGA Cards - Includes Super VGAs, Second Edition" by Richard Ferraro, ISBN 0-201-57025-4, published by Addison-Wesley. This book is by far the most comprehensive VGA/SVGA reference I have seen to date and is more than worth it's price tag. I heartily recommend it to anyone wishing to do any serious graphics programming for the PC. The PC-GPE SVGA section was originally not going to be included in version 1 due to the fact that I have only been able to verify that the info on the Paradise SVGA is correct. I will include it however, in the hope that everyone (and I mean *EVERYONE*) who reads these files and tries out the routines will e-mail me with the results they get so I can make the modifications in time for version 2. I will need to know these things: 1) Your SVGA board name 2) The id and revision number of the chip inside (if possible) 3) What you tried and the results you got. This applies to *all* routines, bank switching, chip detection etc.... I need to know everything! If a routine doesn't work as expected then let me know if it's doing anything at all. "The routine is stuffed you idiot" won't exactly help me much, but "I can only read pixels in bank 0 you idiot" just might...... And of course there's always the chance that I've misunderstood my references so I need to have my mistakes pointed out to me as well. I'm a big boy...I can take it! 旼컴컴컴컴컴컴컴컴컴컴컴컴컫컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴 � Writing to the VGA Ports � 읕컴컴컴컴컴컴컴컴컴컴컴컴켸 Many of the PC-GPE SVGA texts have the PortW Pascal command as follows: PortW[PORTNUM] := VALUE; This command writes a 16 bit word to the port, the same as the asm op code: out dx, ax The effect of this code is the same as the following two Pascal statements: Port[PORTNUM] := Lo(VALUE); Port[PORTNUM + 1] := Hi(VALUE); I'm not sure if this is common to all the PC ports or only works on the VGA. (Perhaps someone could enlighten me?) The PortW command is very handy when writing to the SVGA extended registers. The SVGA register sets are all extensions of the VGA register sets and use an indexed addressing scheme to cut down on the number of ports they use. The texts often have register maps which look similar to the following: PR0A Address Offset A Index : 09h at port 3CEh Read/Write at port 3CFh 旼컴쩡컴쩡컴쩡컴쩡컴쩡컴쩡컴쩡컴� � 7 � 6 � 5 � 4 � 3 � 2 � 1 � 0 � 읕컴좔컴좔컴좔컴좔컴좔컴좔컴좔컴� 읕컴컴컴컴컴쩡컴컴컴컴컴� Bank For this particular map, the register name is PR0A Offset A. To select the register and get it ready for reading and/or writing you write the value 09h to port 3CEh (the index port). The register can then be read from or written to port 3CFh (the read/write port). 旼컴컴컴컴컴컴컴컫컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴 � Bank Switching � 읕컴컴컴컴컴컴컴켸 In real mode, the PC has addresses A000:0000-B000:FFFF allocated for video memory, although most graphics modes only use the A000 segment. If you set an SVGA card to 640x480x256 color mode (for example) then there will be a total of 307200 pixels on the screen. Since each pixel takes up one byte in 256 color modes around 300K of video memory will be used to store the screen data. In most cases all this memory is accessed through the A000 segment. When you initially set the mode, bank 0 on the card will be active and anything you read to or write from this segment will be in the first 64K bytes in video memory (i.e. lines 0-101 and the first 256 bytes in line number 102). If you want to access the next 64K you must switch the card to bank number 1 so that the A000 segment now maps to the second bank, and so forth. The problem here is that each card has a different method of doing the bank switching. The PC-GPE files contain info on how to do the bank switching for a number of the most commonly used SVGA cards. The VESA standard helped inject some sanity into the otherwise chaotic world of SVGA programming by introducing a "standard" method of bank switching for all cards. A note should be made here about bank granularity. In the section above I assumed that bank 0 corresponded to the first 64K, bank 1 to the next etc.. ie each bank has a 64K granularity. This is true for most cards, but some do have smaller granularities (see the table below). The Paradise for instance has a 4K granularity. It's very similar in concept to the PC's segmented memory, segments are 64K long but they have a 16 byte granularity. The Paradise chip's banks are also 64K long, but they have a 4K granularity. All the bank switching code given in the PC-GPE SVGA files adjust for this so that your code can assume the card has a 64K granularity in all cases. 旼컴컴컴컴컴컴컴컫컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� � SVGA Libraries � 읕컴컴컴컴컴컴컴켸 There are a few SVGA libraries available via anonymouse ftp. I haven't had a chance to use any of them yet, but I've heard some of them are pretty good, so they might be worth checking out. Here's two C libraries that I know of: site: ftp.fasttax.com directory: /pc/graphic/scitech/beta filename: svkt44bl.zip site: garbo.uwasa.fi directory: /pc/programming filename: SVGACC20.ZIP 旼컴컴컴컴컴컴컴컴컴쩡컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴 � Common SVGA Cards � 읕컴컴컴컴컴컴컴컴컴� The PC-GPE files contain information on programming the 7 VGA "standards" as covered by Ferraro. According to Ferraro the majority of SVGA cards on the market today conform to one of these standards. The standards are Ati, Chips and Technologies, Genoa, Paradise, Trident, Tseng and Video7. I've also included a file on the VESA specifications (VESASP12.TXT). VESA seems to be the way to go now since public domain drivers are available for most cards and you only need to write one set of graphics drivers if you use it. VESA BIOS calls can be slow however, so if your program needs to do LOTS of bank switching then you may need to work with the cards on a hardware level. The following is a list of common SVGA's along with the chip it is based on, the number of banks the card contains and the modes they support. The GR field is the bank granularity. This information was obtained by examining the configuration files in the shareware program VPIC. VPIC is a great little program which supports numerous graphics file formats as well as all the cards listed below (and a few more). VPIC can be obtained via anonymous ftp from oak.oakland.edu, directory /pub/msdos/gif, filename vpic. I tried to contact the author so I'd feel better about blatently ripping all the info out of his data files but he doesn't seem to have an e-mail address. Are you out there Bob Montgomery? Quite a number of the chip sets in the list are not mentioned in Ferraro. If anyone has information on programming any of them drop me a line. Each mode in the table below has a mode number. To set the mode, load the AX register with this value and do an interrupt 10h. Some modes below have two numbers. In these cases load AX with the first number and BX with the second before calling interrupt 10h. Only 16 and 256 color are presented in the table below. True-color modes are not included in this version. Board Chip Banks Modes Resolution Col GR 컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� Acumos ACUMOS 8 5Eh 640x400 256 64k 5Fh 640x480 256 64k 5Ch 800x256 256 64k 10h 640x350 16 64k 12h 640x480 16 64k 58h 800x600 16 64k 5dh 1024x768 16 64k Ahead A Chip AHEADA 4/8 60h 640x400 256 64k 61h 640x480 256 64k 62h 800x600 256 64k 6Ah 800x600 16 64k 74h 1024x768 16 64k Ahead B Chip AHEADB 8/16 60h 640x400 256 64k 61h 640x480 256 64k 62h 800x600 256 64k 63h 1024x768 256 64k 6Ah 800x600 16 64k 74h 1024x768 16 64k ATI VGA Wonder ATI OLD 4/8 61h 640x400 256 32k 62h 640x480 256 32k 63h 800x600 256 32k 54h 800x600 16 32k 65h 1024x768 16 64k ATI VGA Wonder+ ATI NEW 4/8/16 61h 640x400 256 32k 62h 640x480 256 32k 63h 800x600 256 32k 64h 1024x768 256 32k 54h 800x600 16 32k 55h 1024x768 16 32k ATI Ultra 8514A GA ATI NEW 4/8/16 61h 640x400 256 32k 62h 640x480 256 32k 63h 800x600 256 32k 54h 800x600 16 32k 55h 1024x768 16 32k ATI XL ATI NEW 4/8/16 61h 640x400 256 32k 62h 640x480 256 32k 63h 800x600 256 32k 64h 1024x768 256 32k 54h 800x600 16 32k 55h 1024x768 16 32k Chips & Technology Chips and 4/8 78h 640x400 256 16k Technologies 79h 640x480 256 16k 7Ah 720x540 256 16k 7Bh 800x600 256 16k 70h 800x600 16 16k 71h 960x720 16 16k 72h 1024x768 16 16k Cirrus Logic GD54 VESA 16/64 4F02h,100h 640x400 256 4k 4F02h,101h 640x480 256 4k 4F02h,103h 800x600 256 4k 4F02h,105h 1024x768 256 4k 4F02h,102h 800x600 16 4k 4F02h,104h 1024x768 16 4k Definicon, 16 Bit TSENG 4000 8/16 2dh 640x350 256 64k 2fh 640x400 256 64k 2eh 640x480 256 64k 30h 800x600 256 64k 38h 1024x768 256 64k 29h 800x600 16 64k 37h 1024x768 16 64k 3Dh 1280x1024 16 64k Diamond 24x PARADISE 4/16 5eh 640x400 256 4k 5fh 640x480 256 4k 5ch 800x600 256 4k 60h 1024x768 256 4k 58h 800x600 16 4k 5Dh 1024x768 16 4k 6Ch 1280x960 16 4k 64h 1280x1024 16 4k Diamond Speedstar 24 TSENG 4000 8/16 2dh 640x350 256 64k 2fh 640x400 256 64k 2eh 640x480 256 64k 30h 800x600 256 64k 38h 1024x768 256 64k 29h 800x600 16 64k 37h 1024x768 16 64k Everex EV-673 EVEREX 4/8 70h,13h 640x350 256 64k 70h,14h 640x400 256 64k 70h,15h 512x480 256 64k 70h,30h 640x480 256 64k 70h,31h 800x600 256 64k 70h,02h 800x600 16 64k 70h,20h 1024x768 16 64k Everev 678 TRIDENT 4/8 70h,14h 640x400 256 64k 8800 70h,15h 512x480 256 64k 70h,30h 640x480 256 64k 70h,31h 800x600 256 64k 70h,02h 800x600 16 64k 70h,20h 1024x768 16 64k Everex Vision VGA HC TSENG 4000 8/16 2fh 640x400 256 64k 2eh 640x480 256 64k Genoa 5400 TSENG 3000 4/8 2dh 640x350 256 64k 2eh 640x480 256 64k 30h 800x600 256 64k 29h 800x600 16 64k 37h 1024x768 16 64k Genoa 6400 GENOA 4/8 2bh 640x350 256 64k 2eh 640x480 256 64k 30h 800x600 256 64k 29h 800x600 16 64k 37h 1024x768 16 64k Genoa 7900 24 bit TSENG 4000 8/16 2dh 640x350 256 64k 2fh 640x400 256 64k 2eh 640x480 256 64k 30h 800x600 256 64k 38h 1024x768 256 64k 29h 800x600 16 64k 37h 1024x768 16 64k Headland 1024i HEADLAND 4/8 6F05h,66h 640x400 256 64k 6F05h,67h 640x480 256 64k 6F05h,68h 720x540 256 64k 6F05h,69h 800x600 256 64k 6F05h,61h 720x540 16 64k 6F05h,62h 800x600 16 64k 6F05h,65h 1024x768 16 64k Hi Res 512 ZYMOS 4/8 5ch 640x400 256 64k 5dh 640x480 256 64k 5eh 800x600 256 64k 6ah 800x600 16 64k 5fh 1024x768 16 64k Maxxon TRIDENT 8800 4/8 5ch 640x400 256 64k 5dh 640x480 256 64k 5eh 800x600 256 64k 5bh 800x600 16 64k 5fh 1024x768 16 64k C&T MK82452 CHIPS AND 8 78h 640x400 256 16k TECHNOLOGIES 79h 640x480 256 16k 70h 800x600 16 16k 72h 1024x768 16 16k NCR 77C22 NCR 8/16 5eh 640x400 256 64k 5fh 640x480 256 64k 5ch 800x600 256 64k 62h 1024x768 256 64k 58h 800x600 16 64k 5dh 1024x768 16 64k OAK OAK 8/16 53h 640x480 256 64k 54h 800x600 256 64k 59h 1024x768 256 64k 52h 800x600 16 64k 56h 1024x768 16 64k Orchid Fahrenheight 1280 S3 8/16 4F02h,201h 640x480 256 64k 4F02h,203h 800x600 256 64k 4F02h,205h 1024x768 256 64k 4F02h,202h 800x600 16 64k 4F02h,204h 1024x768 16 64k 4F02h,206h 1280x960 16 64k 4F02h,206h 1280x1024 16 64k Orchid Pro Designer II TSENG 4000 8/16 2dh 640x350 256 64k 2fh 640x400 256 64k 2eh 640x480 256 64k 30h 800x600 256 64k 38h 1024x768 256 64k 29h 800x600 16 64k 37h 1024x768 16 64k Paradise VGA Pro PARADISE 4/16 5eh 640x400 256 4k 5fh 640x480 256 4k 5ch 800x600 256 4k 60h 1024x768 256 4k 58h 800x600 16 4k 5Dh 1024x768 16 4k Primus P2000 GA PRIMUS 8/16 2dh 640x480 256 64k 2bh 800x600 256 64k 31h 1024x768 256 64k 37h 1280x1024 256 64k 2ah 800x600 16 64k 30h 1024x768 16 64k 36h 1280x1024 16 64k Compaq QVision QVISION 8/16 32h 640x480 256 4k 38h 1024x768 256 4k 10h 640x350 16 4k 12h 640x480 16 4k 29h 800x600 16 4k 37h 1024x768 16 4k Realtek RTVGA REALTEK 8/16 25h 640x400 256 64k 26h 640x480 256 64k 27h 800x600 256 64k 28h 1024x768 256 64k 1Fh 800x600 16 64k 21h 1024x768 16 64k 2Ah 1280x1024 16 64k Realtek RTVGA REALTEK 8/16 25h 640x400 256 64k 26h 640x480 256 64k 27h 800x600 256 64k 28h 1024x768 256 64k 1Fh 800x600 16 64k 21h 1024x768 16 64k 2Ah 1280x1024 16 64k S3 Graphics Accelerator S3 8/16 4F02h,201h 640x480 256 64k 4F02h,203h 800x600 256 64k 4F02h,205h 1024x768 256 64k 4F02h,202h 800x600 16 64k 4F02h,204h 1024x768 16 64k 4F02h,206h 1280x960 16 64k STB EM 16 TSENG 4000 8/16 2dh 640x350 256 64k 78h 640x400 256 64k 2eh 640x480 256 64k 30h 800x600 256 64k 38h 1024x768 256 64k 29h 800x600 16 64k 37h 1024x768 16 64k Phoebes TRIDENT 8800CS 4/8 5ch 640x400 256 64k 5dh 640x480 256 64k 5bh 800x600 16 64k 5fh 1024x768 16 64k Maxxon TRIDENT 8800CS 4/8 5ch 640x400 256 64k 5dh 640x480 256 64k 5eh 800x600 256 64k 5bh 800x600 16 64k 5fh 1024x768 16 64k Trident 8900 TRIDENT 8900 8/16 5Ch 640x400 256 64k 5Dh 640x480 256 64k 5Eh 800x600 256 64k 62h 1024x768 256 64k 5Bh 800x600 16 64k 5Fh 1024x768 16 64k Tseng ET-3000 TSENG ET3000 4/8 2dh 640x350 256 64k 2eh 640x480 256 64k 30h 800x600 256 64k 29h 800x600 16 64k 36h 960x720 16 64k 37h 1024x768 16 64k Tseng ET-4000 TSENG ET4000 8/16 2dh 640x350 256 64k 2fh 640x400 256 64k 2eh 640x480 256 64k 30h 800x600 256 64k 38h 1024x768 256 64k 29h 800x600 16 64k 37h 1024x768 16 64k Video 7 VRAM VIDEO7 4/8 6f05h,66h 640x400 256 64k 6f05h,67h 640x480 256 64k 6f05h,68h 720x540 256 64k 6f05h,69h 800x600 256 64k 6f05h,61h 720x540 16 64k 6f05h,62h 800x600 16 64k 6f05h,65h 1024x768 16 64k Western Digital 90C PARADISE 4/8 5eh 640x400 256 4k 5fh 640x480 256 4k 5ch 800x600 256 4k 58h 800x600 16 4k 5Dh 1024x768 16 4k