386-20/25 Motherboard Settings and Configuration
UNIDENTIFIED
386-20/25
Processor | 80386SX (exact location unidentified) |
Processor Speed | 20/25MHz |
Chip Set | Unidentified |
Maximum Onboard Memory | 10MB (on external memory card) |
Cache | None |
BIOS | Unidentified |
Dimensions | 228mm x 220mm |
I/O Options | External memory card |
NPU Options | 80387SX (exact location unidentified) |
CONNECTIONS | |||
Function | Label | Function | Label |
External battery | X1 | Turbo LED | x8 |
Reset switch | X4 | Speaker | X17 |
Status port | X5 | Turbo switch | X22 |
Power LED & keylock | x6 | External memory card | SL1 |
USER CONFIGURABLE SETTINGS | |||
Setting | Label | Position | |
» | Speed select through keyboard | S1 | Pins 2 & 3 closed |
Speed select through turbo switch | S1 | Pins 1 & 2 closed | |
» | I/O slot wait state select 4 wait states | S2 | Pins 1 & 2 closed |
I/O slot wait state select 6 wait states | S2 | Pins 2 & 3 closed | |
» | Factory configured - do not alter | S5 | N/A |
» | Factory configured - do not alter | SW1/1 | N/A |
» | NPU disabled | SW1/2 | Off |
NPU enabled | SW1/2 | On | |
» | Floppy drive speed does not affect CPU speed | SW1/3 | Off |
Floppy drive speed at CPU speed 8MHz | SW1/3 | On | |
» | Monitor type select monochrome | SW1/4 | Off |
Monitor type select color | SW1/4 | On | |
» | Factory configured - do not alter | X23 | N/A |
DRAM | ||||
Size | Bank 0 | Bank 1 | Bank 2 | Bank 3 |
1MB | 1MB kit | None | None | None |
1MB | 1MB kit | None | None | None |
2MB | 1MB kit | None | 1MB kit | None |
2MB | 1MB kit | None | 1MB kit | None |
4MB | None | 4MB kit | None | None |
5MB | 1MB kit | 4MB kit | None | None |
6MB | 1MB kit | 4MB kit | 1MB kit | None |
6MB | 1MB kit | 4MB kit | 1MB kit | None |
8MB | None | 4MB kit | None | 4MB module |
9MB | 1MB kit | 4MB kit | None | 4MB module |
10MB | 1MB kit | 4MB kit | 1MB kit | 4MB module |
10MB | 1MB kit | 4MB kit | 1MB kit | 4MB module |
Note: Banks are located on the external memory card. | ||||
DRAM SWITCH | ||||
Size | SW1/5 | SW1/6 | SW1/7 | SW1/8 |
1MB | On | On | On | On |
1MB | On | On | On | Off |
2MB | On | On | Off | On |
2MB | On | On | Off | Off |
4MB | On | Off | On | On |
5MB | On | Off | On | Off |
6MB | On | Off | Off | On |
6MB | On | Off | Off | Off |
8MB | Off | On | On | On |
9MB | Off | On | On | Off |
10MB | Off | On | Off | On |
10MB | Off | On | Off | Off |
BIOS | ||
Setting | S3 | S4 |
27128 | Pins 1 & 2 closed | Pins 1 & 2 closed |
27256 | Pins 2 & 3 closed | Pins 1 & 2 closed |
27512 | Pins 2 & 3 closed | Pins 2 & 3 closed |
MISCELLANEOUS TECHNICAL NOTE |
The location of pin 1 on all jumpers and the switch is unidentified. |
My Books
