TANDY/RADIO SHACK

EGA/CGA GRAPHICS BOARD (250-3048)

Card Type

Video card

Video Processor

6845

Maximum Onboard Memory

256KB DRAM

Data Bus

8-bit ISA

Video Types Supported

Plantronics, EGA

Highest Resolution Supported

720 x 350

CONNECTIONS

Function

Label

Function

Label

Not used

J1

9-pin video out connector

J3

Not used

J2

Not used

J4

USER CONFIGURABLE SETTINGS

Setting

Label

Position

»

Factory configured - do not alter

P1

Unidentified

»

EGA mode base I/O address set to 3D0h

P3

Pins 1 & 2 closed

 

EGA mode base I/O address set to 2D0h

P3

Pins 2 & 3 closed

»

Card will use EGA mode by default

SW1/5

Off

 

Card will use CGA or monochrome mode by default

SW1/5

On

Note:SW1/5 must always be turned off for Tandy SX and TX model mainboards.

MONITOR TYPE SELECTION

Setting

P2

SW1/1

SW1/2

SW1/3

SW1/4

Monochrome

Pins 2 & 3

Off

Off

On

Off

CGA

Pins 2 & 3

Off

Off

Off

On

EGA

Pins 1 & 2

Off

On

On

Off

Note:Pins designated are in the closed position.