Tseng Super VGA
ET3000-AX 512k 8/16 bit Main chip
-BX 512k 8 bit
-Bp 256k 8 bit Basic chip
ET4000 1M 8/16 bit
Registers:
102h: Microchannel Setup Control
bit 0 Disable Card if set
3C0h index 16h: ATC Miscellaneous
(Write data to 3C0h, Read from 3C1h (May not be needed))
bit 4,5 High resoloutionn 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
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)
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
Adress 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 adress bit 16
1 Display start adress bit 16
2 Zoom start adress bit 16
3d4h index 24h (R/W): Compatability 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 adress bits 16-17
2-3 Cursor start adress 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 adressing 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
46E8h (R): Video Subsystem Enable Register
bit 3 Enable VGA if set
3C4h index 05 used.
3CBh used. PEL Add/Dat. ??
3CEh index 0Dh-0Eh 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:
old:=port[$3CD];
port[$3cd]:=$55;
new:=port[$3cd];
port[$3cd]:=old;
if new=$55 then Tseng Chip !!!
Identify Tseng 4000:
if odd(port[$3cc]) then base:=$3d4 else base:=$3b4;
port[base]:=$33;old_value:=port[base+1];
new_value:=old_value xor 15;
port[base+1]:=new_value;
value:=port[base+1];
port[base+1]:=old_value;
if value=new_value then ET4000 chip !!!
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 recomanded, 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 recomanded, 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)
See Hicolor.doc for information about the Sierra HiColor RAMDAC.