SD 550 Motherboard Settings and Configuration

Processor	80286 (exact location unidentified)
Processor Speed	12MHz
Chip Set	Unidentified
Maximum Onboard Memory	1MB
Cache	None
BIOS	Award
Dimensions	406mm x 406mm
I/O Options	Floppy drive interface, parallel port, serial ports (2)
NPU Options	80287 (exact location unidentified)

CONNECTIONS
Function	Label	Function	Label
Serial port	CN11	Power LED & keylock	J13
Serial port	CN12	Speaker	J14
Parallel port	CN13	External battery	J15
Keyboard connector	J11	Floppy drive interface	J17

USER CONFIGURABLE SETTINGS
Setting		Label	Position
»	Jumper information unavailable	J12	N/A
	Parallel port enabled	JP11	Closed
	Parallel port disabled	JP11	Open
	Floppy drive interface enabled	JP12	Closed
	Floppy drive interface disabled	JP12	Open
	Serial port 1 enabled	JP13	Closed
	Serial port 1 disabled	JP13	Open
	Serial port 2 enabled	JP14	Closed
	Serial port 2 disabled	JP14	Open
	BIOS type select 27256	JP15	Closed
	BIOS type select 27128	JP15	Open
	NPU speed select 16MHz	JP17	Pins 1 & 2 closed
	NPU speed select 25MHz	JP17	Pins 2 & 3 closed
	Drive type select dual speed	JP19	Closed
	Drive type select single speed	JP19	Open
	Precomp value select 187ns	JP20	Closed
	Precomp value select 125ns	JP20	Open
	Floppy drive address select secondary	JP22	Closed
	Floppy drive address select primary	JP22	Open
	Monitor type select color	SW10	Up
	Monitor type select monochrome	SW10	Down

DRAM
Size	Bank 0	Bank 1	Bank 2	Bank 3
640KB	(9) 41256	(9) 41256	(9) 4164	(9) 4164
1MB	(9) 41256	(9) 41256	(9) 41256	(9) 41256
Note: The orientation of the banks is unidentified.

DRAM JUMPER
Size	JP16
640KB	Closed
1MB	Open

DRAM WAIT STATE
Setting	JP21
0 wait states	Closed
1 wait state	Open