HP 520 5/XX, Technical Reference Manual

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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
Type
Resolution
No. of
Colors
Vertical
Refresh (Hz)
Horizontal
Refresh (kHz)
Dot Clock
(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