DRS M50/M55 Motherboard Settings and Configuration

Processor	80386SX
Processor Speed	16/20MHz
Chip Set	Unidentified
Max. Onboard DRAM	8MB
Cache	None
BIOS	Unidentified
Dimensions	330mm x 218mm
I/O Options	Floppy drive interface, IDE interface, parallel port, serial ports (2), VGA port, riser slot
NPU Options	80387SX

CONNECTIONS
Purpose	Location	Purpose	Location
Reset switch	CN1	Serial port 1	P1
LED’s & security lock	CN2	Parallel port	P2
Keyboard/mouse connector	CN3	Serial port 2	P3
IDE interface	JP1	VGA port (on VGA board)	P4
Floppy drive interface	JP2	Riser slot	SL1

USER CONFIGURABLE SETTINGS (MAINBOARD)
Function		Jumper	Position
	Password enabled	J3	Pins 1 & 2 closed
	Password disabled	J3	Pins 2 & 3 closed
	Security lock enabled	J9	Open
	Security lock disabled	J9	Closed

DRAM CONFIGURATION
Size	Bank 0	Bank 1	Bank 2	Bank 3
2MB	(2) 1M x 9	None	None	None
4MB	(2) 1M x 9	(2) 1M x 9	None	None
8MB	(2) 1M x 9	(2) 1M x 9	(2) 1M x 9	(2) 1M x 9

CPU SPEED CONFIGURATION
Speed	J4	J5
16MHz	Pins 2 & 3 closed	Pins 2 & 3 closed
20MHz	Pins 1 & 2 closed	Pins 1 & 2 closed

USER CONFIGURABLE SETTINGS (VGA BOARD)
Function		Jumper	Position
»	On board video enabled	J1	Closed
	On board video disabled	J1	Open
»	VGA IRQ9 enabled	J4	Closed
	VGA IRQ9 disabled	J4	Open
»	VGA BIOS enabled	SW1	Pins 1 & 2 closed
	VGA BIOS disabled	SW1	Pins 2 & 3 closed