EVEREX SYSTEMS, INC.
SYSTEM 3900 (EV-1851)
| 
 Processor  | 
 80386DX  | 
| 
 Processor Speed  | 
 25/33MHz  | 
| 
 Chip Set  | 
 C & T  | 
| 
 Max. Onboard DRAM  | 
 8MB  | 
| 
 Cache  | 
 64KB  | 
| 
 BIOS  | 
 AMI  | 
| 
 Dimensions  | 
 355mm x 304mm  | 
| 
 I/O Options  | 
 32-bit external memory card slot  | 
| 
 NPU Options  | 
 80387/3167  | 
| 
 CONNECTIONS  | |||
| 
 Purpose  | 
 Location  | 
 Purpose  | 
 Location  | 
| 
 Speaker  | 
 J17  | 
 Keylock  | 
 J18 pin 9  | 
| 
 Power LED  | 
 J18 pin 1  | 
 External battery connector  | 
 J22  | 
| 
 Turbo LED  | 
 J18 pin 2  | 
 Speaker enable/disable switch  | 
 J23  | 
| 
 Reset switch  | 
 J18 pin 6  | 
 32-bit external memory card  | 
 S1  | 
| 
 USER CONFIGURABLE SETTINGS  | |||
| 
 Function  | 
 Jumper  | 
 Position  | |
| » | 
 DRAM speed select 4 wait states  | 
 J15  | 
 pins 1 & 2 closed  | 
| 
 DRAM speed select 3 wait states  | 
 J15  | 
 pins 2 & 3 closed  | |
| » | 
 NPU mode select 1 wait state  | 
 J16  | 
 pins 1 & 2 closed  | 
| 
 NPU mode select 0 wait states  | 
 J16  | 
 pins 2 & 3 closed  | |
| » | 
 Factory configured - do not alter  | 
 J19  | 
 Open  | 
| 
 DRAM CONFIGURATION  | ||||
| 
 Size  | 
 Bank 0  | 
 Bank 1  | 
 Bank 2  | 
 Bank 3  | 
| 
 1MB  | 
 (4) 256K x 9  | 
 NONE  | 
 NONE  | 
 NONE  | 
| 
 2MB  | 
 (4) 256K x 9  | 
 (4) 256K x 9  | 
 NONE  | 
 NONE  | 
| 
 4MB  | 
 (4) 256K x 9  | 
 (4) 256K x 9  | 
 (4) 256K x 9  | 
 (4) 256K x 9  | 
| 
 4MB  | 
 (4) 1M x 9  | 
 NONE  | 
 NONE  | 
 NONE  | 
| 
 8MB  | 
 (4) 1M x 9  | 
 (4) 1M x 9  | 
 NONE  | 
 NONE  | 
| 
 16MB  | 
 (4) 1M x 9  | 
 (4) 1M x 9  | 
 (4) 1M x 9  | 
 (4) 1M x 9  | 
| 
 Note:Banks 2 & 3 are used when a 32-bit external memory card is installed.  | ||||
| 
 CACHE CONFIGURATION  | |
| 
 Size  | 
 Bank 0  | 
| 
 64KB  | 
 (8) 64K x 1  | 
| 
 Note:Cache is factory installed and is not configurable.  | |
| 
 CMOS CONFIGURATION  | ||||||||
| 
 Setting  | 
 W1  | 
 W2  | 
 W3  | 
 W4  | 
 W5  | 
 W6  | 
 W7  | 
 W8  | 
| 
 Internal  | 
 2 & 3  | 
 2 & 3  | 
 2 & 3  | 
 2 & 3  | 
 2 & 3  | 
 2 & 3  | 
 2 & 3  | 
 2 & 3  | 
| 
 External  | 
 1 & 2  | 
 1 & 2  | 
 1 & 2  | 
 1 & 2  | 
 1 & 2  | 
 1 & 2  | 
 1 & 2  | 
 1 & 2  | 
| 
 Note: Pins designated should be in the closed position.  | ||||||||