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.  | |||||