ET3000-AX 512k 8/16 bit Main chip
-BX 512k 8 bit
-Bp 256k 8 bit Basic chip
ET4000 1M 8/16 bit
ET4000/X32 will be released in '92 supporting 24bit colors, 4MB DRAM or VRAM
and built-in accelerator.
Registers:
102h: Microchannel Setup Control
bit 0 Disable Card if set
3BFh (R/W): Hercules Compatability register
3C0h index 16h: ATC Miscellaneous
(Write data to 3C0h, Read from 3C1h (May not be needed))
bit 4,5 High resolution timings.
3C3h (R/W): Microchannel Video Subsystem Enable Register:
bit 0 Enable Microchannel VGA if set
3C4h index 6 (R/W): Zoom Control (ET3000 Only)
bit 0-2 Yzoom factor 0=1:1
4-6 Xzoom factor 0=1:1
7 Hardware zoom enabled if set
3C4h index 7 (R/W): TS Auxiliary Mode
bit 0 (ET3000 Only) Switch Normal Window if set (Text/Graph)
1 (ET3000 Only) Switch Zoom Window if set (Text/Graph)
2 (ET3000 Only) Switch Split Window if set (Text/Graph)
4 (ET3000 Only) If set 8 simultaneous fonts are enabled,
using bit 3,4,6 of each attribute byte
to select the font.
3,5 Rom Bios Enable/Disable:
0 0 C000-C3FF Enabled
0 1 Rom disabled
1 0 C000-C5FF,C680-C7FF Enabled
1 1 C000-C7FF Enabled
6 MCLK/2 if set
7 VGA compatible if set EGA else.
3CBh (R/W): PEL Address/Data Wd
3CDh (R/W): Segment Select
bit 0-2 (ET3000) 64k Write bank nr
3-5 (ET3000) 64k Read bank nr
6-7 (ET3000) Segment Configuration.
0 128K segments
1 64K segments
2 1M linear memory
0-3 (ET4000) 64k Write bank nr (0..15)
4-7 (ET4000) 64k Read bank nr (0..15)
3CEh index Dh (R/W): Microsequencer Mode
3CEh index Eh (R/W): Microsequencer Reset
3d4h index 1Bh (R/W): X Zoom Start Address (ET3000 Only)
bit 0-7 Offset of Zoom window start in character clocks
(8 pixels) from left edge
3d4h index 1Ch (R/W): X Zoom End (ET3000 Only)
bit 0-7 Offset of Zoom window end in char clocks from left edge
3d4h index 1Dh (R/W): Y Zoom Start Address (ET3000 Only)
bit 0-7 Start line of zoom window bit 0-7
3d4h index 1Eh (R/W): Y Zoom End Address (ET3000 Only)
bit 0-7 (ET3000 Only) End line of zoom window bit 0-7
3d4h index 1Fh (R/W): Y Zoom Start and End High (ET3000 Only)
bit 0-2 End line of zoom window bit 8-10
3-5 Start line of zoom window bit 8-10
3d4h index 20h (R/W): Zoom Start Address Low (ET3000 Only)
bit 0-7 Zoom Start Address bit 0-7
Address of Zoom data
3d4h index 21h (R/W): Zoom Start Address Middle (ET3000 Only)
bit 0-7 Zoom Start Address bit 8-15
3d4h index 23h (R/W): Extended start ET3000 (ET3000 Only)
bit 0 Cursor start address bit 16
1 Display start address bit 16
2 Zoom start address bit 16
3d4h index 24h (R/W): Compatibility Control
bit 0 Enable Clock Translate
1 Additional Master Clock Select
2 Enable tri-state for all output pins
3 Enable input A8 of 1MB DRAMs
4 Reserved
5 Enable external ROM CRTC translation
6 Enable Double Scan and Underline Attribute
7 CGA/MDA/Hercules
3d4h index 25h (R/W): Overflow High ET3000 (ET3000 Only)
bit 0 Vertical Blank Start bit 10
1 Vertical Total Start bit 10
2 Vertical Display End bit 10
3 Vertical Sync Start bit 10
4 Line Compare bit 10
5-6 Reserved
7 Vertical Interlace if set
3d4h index 32h (R/W): RAS/CAS Video Config
Ram timing, System clock and Ram type. Sample values:
00h VRAM 80nsec
09h VRAM 100nsec
00h VRAM 28MHz
08h VRAM 36MHz
70h DRAM 40MHz
3d4h index 33h (R/W): Extended start ET4000 (ET4000 Only)
bit 0-1 Display start address bits 16-17
2-3 Cursor start address bits 16-17
Can be used to ID ET4000
3d4h index 34h (R/W): Compatibility Control Register
bit 3 if set Video Subsystem Enable Register at 46E8h
else at 3C3h.
3d4h index 35h (R/W): Overflow High ET4000 (ET4000 Only)
bit 0 Vertical Blank Start Bit 10
1 Vertical Total Bit 10
2 Vertical Display End Bit 10
3 Vertical Sync Start Bit 10
4 Line Compare Bit 10
5 Gen-Lock Enabled if set (External sync)
6 Read/Modify/Write Enabled if set. Currently not implemented.
7 Vertical interlace if set
3d4h index 36h (R/W): Video System Configuration 1
bit 3 16 bit wide fonts if set, else 8 bit wide
4 (ET4000 Only) Linear addressing if set
Video Memory is mapped as a 1 Meg block above 1MB.
6 16 bit data path (video memory) if set
7 16 bit data (I/O operations) if set
3d4h index 37h (R/W): Video System Configuration 2
bit 0-1 Memory size 0,1=256k, 2=512k, 3=1M ???
3 Clear if 64kx4 RAMs ???
if set RAM size = (bit 0-1)*256k
else RAM size = (bit 0-1)* 64k
4 16 bit ROM access if set
5 Memory bandwidth (0 better than 1) ???
7 VRAM installed if set DRAM else.
bit 6? Block read ahead (BRA) if clear
3d4h index 3Fh (R/W):
bit 7 This bit seems to be bit 8 of the CRTC offset register (3d4h index 13h).
3d8h (R/W): Display Mode Control
46E8h (R): Video Subsystem Enable Register
bit 3 Enable VGA if set
3C4h index 05 used.
Bank Switching:
64k banks are selected by the Segment Select Register at 3CDh.
Both a Read and a Write segment can be selected.
Hardware Zoom (ET3000 Only).
The ET3000 can zoom a part of display memory in a window.
The display memory position and window position are selected
by 3d4h index 1Bh to 21h.
Identify Tseng Chipset:
outp($3BF,3);
outp($3D8,$A0); {Enable ET4000 extensions}
if tstrg($3CD,$3f) then
if testinx2(base,$33,$f) then Tseng 4000
else Tseng 3000;
Video Modes:
8 T 132 25 2 (STB only)
Ah T 132 44 2
18h T 132 44 4 (8x8) B000
19h T 132 25 4 (9x14) B000
1Ah T 132 28 4 (9x13) B000
22h T 132 44 16 (8x8)
23h T 132 25 16 (8x14)
24h T 132 28 16 (8x13)
25h G 640 480 16 planar
26h T 80 60 16 (8x8)
27h G 720 512 16 planar (Tseng recommended, few boards)
29h G 800 600 16 planar
2Ah T 100 40 16 planar
2Dh G 640 350 256 packed
2Eh G 640 480 256 packed
2Fh G 640 400 256 packed (ET4000 Only)
2Fh G 720 512 256 packed (Tseng recommended, few boards)
30h G 800 600 256 packed
36h G 960 720 16 planar (STB only)
37h G 1024 768 16 planar
38h G 1024 768 256 packed (ET4000 Only)
3Dh G 1280 1024 16 planar (newer ET4000s)
3Eh G 1280 960 16 planar (Definicon)
3Eh G 640 480 32k Sierra 15-bit (Compaq Qvision)
BIOS extensions (Tseng 4000 Sierra HiColor DAC):
----------1010E0-----------------------------
INT 10 - VIDEO - SpeedStar 24 - SET TrueColor GRAPHICS MODE
AX = 10E0h
BL = 2Eh
Return: AX = 0010h if successfull
other on error
Enters 24bit 640x480 mode if SS24 DAC present.
Video memory is NOT cleared.
Each line uses 2048 bytes with only 640x3=1920 bytes actually used.
So that a line can never cross a 64K border.
----------1010F0-----------------------------
INT 10 - VIDEO - Tseng ET-4000 BIOS - SET HiColor GRAPHICS MODE
AX = 10F0h
BL = video mode (see also AH=00h)
32768-color modes:
13h = 320x200
2Dh = 640x350
2Eh = 640x480
2Fh = 640x400
30h = 800x600
3Eh = 640x480 16M colors (Genoa 7900)
16M color modes:
3Eh = 640x480 (Genoa 7900)
BX = 2DFFh = 640x350 (MEGAVGA/2)
2EFFh = 640x480 (MEGAVGA/2)
2FFFh = 640x400 (MEGAVGA/2)
Return: AX = 0010h if successful
other on error
SeeAlso: AX=10F1h
----------1010F1-----------------------------
INT 10 - VIDEO - Tseng ET-4000 BIOS - GET DAC TYPE
AX = 10F1h
Return: AX = 0010h if successful, errorcode if not
BL = type of digital/analog converter
00h normal VGA DAC
01h Sierra SC1148x HiColor DAC
(Diamond SpeedStar 24:)
02h New SS24 DAC (16M colors)
(MEGAVGA/2 BIOS:)
02h Sierra Mark2 (15-bit) or Mark3 (16-bit) DAC
03h ATT20c491 or 492 15/16/24 bit HiColor DAC
04h AcuMos ADAC1 (15/16/24 bit)
else other HiColor DAC
SeeAlso: AX=10F0h
----------1010F2-----------------------------
INT 10 - VIDEO - Tseng ET-4000 BIOS - GET/SET HiColor MODE
AX = 10F2h
BL = 00h Get current HiColor mode
01h Set 15bit HiColor mode
02h Set 16bit HiColor mode
Return: AX = 0010h if successfull, errorcode if not
BL = Current HiColor mode:
00h Not in HiColor mode or not a HiColor DAC
01h 15-bit RGB mode
02h 16-bit RGB mode
03h 24-bit RGB mode
Note: Set HiColor mode (BL=1 or 2) only works if already in some HiColor mode.
Notes:
The sequence:
port[$3BF]:=3;
port[$3D8]:=$A0;
is apparently needed to enable the extensions in the Tseng 4000.
Most BIOSes do this by default, but some such as the Sigma VGA Legend
requires this sequence.
Let me know if you encounter any other examples.
