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# 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
IMG IMG 1
+------------------------------------------------------------+
| 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 | P1 | Unidentified |
| | alter | | |
|---+---------------------------------+-------+--------------|
| » | EGA mode base I/O address set | P3 | Pins 1 & 2 |
| | to 3D0h | | closed |
|---+---------------------------------+-------+--------------|
| | EGA mode base I/O address set | P3 | Pins 2 & 3 |
| | to 2D0h | | closed |
|---+---------------------------------+-------+--------------|
| » | Card will use EGA mode by | SW1/5 | Off |
| | default | | |
|---+---------------------------------+-------+--------------|
| | Card will use CGA or monochrome | SW1/5 | On |
| | mode by default | | |
|------------------------------------------------------------|
| 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. |
+------------------------------------------------------------+