5 Video Controllers

The Integrated Ultra VGA Video Controller

S3 Trio 64 Video Memory

The S3 Trio 64 PnP integrated video subsystem has 1 MB of video DRAM preinstalled on the system board, and provides two sockets for the installation of a pair of 512KB video DRAM chips, to upgrade to video memory to 2 MB. The installed video memory capacity is detected automatically by the BIOS.

Normally, the controller gives 32-bit video memory access, with 1 MB of video RAM fitted. This is increased to 64-bit access when the additional 1 MB upgrade is installed.

When the upgrade modules are installed, care must be exercised to align the tapered end of the module with the tapered end of the socket on the system board. A special extraction tool (5041-2553) is needed when removing the modules.

S3 Trio 64 Video Modes

The video subsystem is responsible for generating video data (which is placed in video memory) to be sent to the display.

The following table details the Standard and Enhanced Video Graphics Array (VGA) modes which are currently implemented in the video BIOS. These modes are supported by standard BIOS functions; that is, the video BIOS (which is mapped contiguously in the address range C0000h to C7FFFh) contains all the routines required to configure and access the video subsystem.

Standard VGA Modes (S3 Trio 64)

Mode No.

Standard

Interface

Resolution

No. of

Vertical

Horizontal

Dot Clock

Type

Colors

Refresh (Hz)

Refresh (kHz)

(MHz)

 

 

 

 

 

 

 

 

 

 

 

00h

VGA

text

40 x 25 chars

b/w

70

31.5

25.175

 

 

 

 

 

 

 

 

00h

VGA

text

40 x 25 chars

b/w

70

31.5

25.175

 

 

 

 

 

 

 

 

00h+

VGA

text

40 x 25 chars

b/w

70

31.5

28.322

 

 

 

 

 

 

 

 

01h

VGA

text

40 x 25 chars

16

70

31.5

25.175

 

 

 

 

 

 

 

 

01h

VGA

text

40 x 25 chars

16

70

31.5

25.175

 

 

 

 

 

 

 

 

01h+

VGA

text

40 x 25 chars

16

70

31.5

28.322

 

 

 

 

 

 

 

 

02h

VGA

text

80 x 25 chars

b/w

70

31.5

25.175

 

 

 

 

 

 

 

 

02h

VGA

text

80 x 25 chars

b/w

70

31.5

25.175

 

 

 

 

 

 

 

 

02h+

VGA

text

80 x 25 chars

b/w

70

31.5

28.322

 

 

 

 

 

 

 

 

03h

VGA

text

80 x 25 chars

16

70

31.5

25.175

 

 

 

 

 

 

 

 

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