UNITRON COMPUTER, INC.
486SX SYSTEM
Processor | 80486SX/80486DX |
Processor Speed | 25/33MHz |
Chip Set | UMC |
Max. Onboard DRAM | 32MB |
SRAM Cache | 32/128KB |
BIOS | Phoenix |
Dimensions | 346mm x 218mm |
I/O Options | Floppy drive interface, game port, IDE interface, modem interface, parallel port, serial port (2), VGA port |
NPU Options | 4167 (location unverified) |
CONNECTIONS | |||
Purpose | Location | Purpose | Location |
Game port | C1 | IDE interface | J22 |
VGA port | C2 | Modem interface | J23 |
Parallel port | C3 | Turbo LED | J26 |
Serial port 2 | C4 | Power LED | J28 |
Serial port 1 | C5 | Floppy drive interface | J31 |
Fan power | J3 |
USER CONFIGURABLE SETTINGS | |||
Function | Jumper | Position | |
» | Serial port 1 (CN5) enabled | J18 | pins 1 & 2 closed |
Serial port 1 (CN5) disabled | J18 | pins 2 & 3 closed | |
» | Serial port 1 (CN5) select COM1 (I/O address 3F8-3FFh) | J19 | pins 1 & 2 closed |
Serial port 1 (CN5) select COM3 (I/O address 3E8-3EFh) | J19 | pins 2 & 3 closed | |
» | Parallel port (C3) select LPT1 interrupt IRQ7 at 378-37F | J20 | pins 1 & 2 closed |
Parallel port (C3) select LPT2 interrupt IRQ5 at 278-27F | J20 | pins 2 & 3 closed | |
» | Parallel port (CN3) enabled | J21 | pins 1 & 2 closed |
Parallel port (CN3) disabled | J21 | pins 2 & 3 closed | |
» | IDE interface (J22) enabled | J25 | pins 1 & 2 closed |
IDE interface (J22) disabled | J25 | pins 2 & 3 closed | |
» | Floppy drive interface (J31) enabled | J27 | pins 1 & 2 closed |
Floppy drive interface (J31) disabled | J27 | pins 2 & 3 closed | |
» | Serial port 2 (CN4) select COM2 (I/O address 2F8-2FFh) | J29 | pins 1 & 2 closed |
Serial port 2 (CN4) select COM4 (I/O address 2E8-2EFh) | J29 | pins 2 & 3 closed | |
» | Serial port 2 (CN4) enabled | J30 | pins 1 & 2 closed |
Serial port 2 (CN4) disabled | J30 | pins 2 & 3 closed |
DRAM CONFIGURATION | ||
Size | Bank 0 | Bank 1 |
1MB | (1) 256K x 36 | NONE |
2MB | (1) 256K x 36 | (1) 256K x 36 |
3MB | (1) 512K x 36 | (1) 256K x 36 |
4MB | (1) 1M x 36 | NONE |
5MB | (1) 256K x 36 | (1) 1M x 36 |
8MB | (1) 1M x 36 | (1) 1M x 36 |
12MB | (1) 2M x 36 | (1) 1M x 36 |
16MB | (1) 2M x 36 | (1) 2M x 36 |
32MB | (1) 4M x 36 | (1) 4M x 36 |
CPU TYPE CONFIGURATION | ||
CPU | JP1 | JP2 |
80486DX | pins 1 & 2 closed | pins 1 & 2 and 3 & 4 closed |
80486SX | open | pins 2 & 3 closed |
Note:The location of jumpers JP1 and JP2 is unknown. |
SRAM JUMPER CONFIGURATION | |||||
Size | J7 | J10 | J11 | J13 | J14 |
32KB | open | pins 1 & 2 | pins 1 & 2 | pins 1 & 2 | pins 1 & 2 |
128KB | closed | pins 2 & 3 | pins 2 & 3 | pins 2 & 3 | pins 2 & 3 |
Note:Pins designated should be in the closed postion. |
SRAM CONFIGURATION | |||
Size | Cache SRAM | Location | TAG |
32KB | (4) 8K x 8 | CACHE | (1) 8K x 8 |
128KB | (4) 32K x 8 | CACHE | (1) 32K x 8 |
Note:This configuartion is unverified. |
VRAM CONFIGURATION | ||
Size | VRAM | Location |
256KB | (2) 44256 | Bank 0 |
512KB | (4) 44256 | Banks 0 & 1 |
1MB | (8) 44256 | Banks 0, 1, 2 and 3 |