STEP PLUS 486 (EV-18216) Motherboard Settings and Configuration

Processor	80486SX/80487SX/80486DX/80486DX2/Pentium Overdrive
Processor Speed	25/33/40/50(internal)/50/66(internal)MHz
Chip Set	Unidentified
Max. Onboard DRAM	64MB
Cache	64/128/256KB
BIOS	Unidentified
Dimensions	330mm x 218mm
I/O Options	Floppy drive interface, IDE interface, SCSI connector, parallel port, serial ports (2), VGA port, microphone port, LAN port, CD-ROM auxiliary in, riser slot
NPU Options	None

CONNECTIONS
Purpose	Location	Purpose	Location
LAN port	CN1	Power LED	J4
Serial port 2	CN2	IDE interface LED	J5
Parallel port	CN3	Keylock	J6
Microphone port	CN4	Speaker	J7
Speaker port	CN5	IDE interface	J9
Serial port 1	CN6	SCSI interface	J10
Floppy drive interface	CN7	CD-ROM auxiliary in	J14
Speaker button	J1	VGA port	J15
Reset switch	J2	Riser slot	SL1

USER CONFIGURABLE SETTINGS
Function		Jumper	Position
»	CMOS memory normal operation	JP5	Open
	CMOS memory clear	JP5	Closed
»	On board VGA IRQ9 disabled	JP8	Open
	On board VGA IRQ9 enabled	JP8	Closed
»	IDE interface enabled	JP9	Closed
	IDE interface disabled	JP9	Open
»	SCSI IRQ select IRQ12	JP12	pins 2 & 3 closed
	SCSI IRQ select IRQ10	JP12	pins 1 & 2 closed
»	Parallel port IRQ select IRQ7	JP14	pins 1 & 2 closed
	Parallel port IRQ select IRQ5	JP14	pins 2 & 3 closed
»	Flash BIOS normal mode	SW1	On
	Flash BIOS programming mode	SW1	Off

DRAM CONFIGURATION
Size	Bank 0	Bank 1	Bank 2	Bank 3
1MB	(1) 256K x 36	NONE	NONE	NONE
2MB	(1) 512K x 36	NONE	NONE	NONE
3MB	(1) 512K x 36	(1) 256K x 36	NONE	NONE
4MB	(1) 512K x 36	(1) 512K x 36	NONE	NONE
4MB	(1) 1M x 36	NONE	NONE	NONE
5MB	(1) 512K x 36	(1) 512K x 36	(1) 256K x 36	NONE
6MB	(1) 512K x 36	(1) 512K x 36	(1) 512K x 36	NONE
6MB	(1) 512K x 36	(1) 1M x 36	NONE	NONE
7MB	(1) 512K x 36	(1) 512K x 36	(1) 512K x 36	(1) 256K x 36
8MB	(1) 512K x 36	(1) 512K x 36	(1) 512K x 36	(1) 512K x 36
8MB	(1) 1M x 36	(1) 1M x 36	NONE	NONE
8MB	(1) 2M x 36	NONE	NONE	NONE
8MB	(1) 512K x 36	(1) 512K x 36	(1) 1M x 36	NONE
10MB	(1) 512K x 36	(1) 2M x 36	NONE	NONE
10MB	(1) 512K x 36	(1) 1M x 36	(1) 1M x 36	NONE
12MB	(1) 1M x 36	(1) 1M x 36	(1) 1M x 36	NONE
12MB	(1) 1M x 36	(1) 2M x 36	NONE	NONE
12MB	(1) 512K x 36	(1) 512K x 36	(1) 2M x 36	NONE
12MB	(1) 512K x 36	(1) 512K x 36	(1) 2M x 36	NONE
14MB	(1) 512K x 36	(1) 1M x 36	(1) 2M x 36	NONE
16MB	(1) 2M x 36	(1) 2M x 36	NONE	NONE
16MB	(1) 1M x 36	(1) 1M x 36	(1) 2M x 36	NONE
16MB	(1) 1M x 36	(1) 1M x 36	(1) 1M x 36	(1) 1M x 36
16MB	(1) 4M x 36	NONE	NONE	NONE
18MB	(1) 512K x 36	(1) 2M x 36	(1) 2M x 36	NONE
20MB	(1) 1M x 36	(1) 4M x 36	NONE	(1) 2M x 36
20MB	(1) 1M x 36	(1) 2M x 36	(1) 2M x 36	NONE

DRAM CONFIGURATION (CON’T)
Size	Bank 0	Bank 1	Bank 2	Bank 3
20MB	(1) 1M x 36	(1) 1M x 36	(1) 2M x 36	(1) 1M x 36
24MB	(1) 1M x 36	(1) 1M x 36	(1) 4M x 36	NONE
26MB	(1) 512K x 36	(1) 2M x 36	(1) 2M x 36	NONE
28MB	(1) 1M x 36	(1) 2M x 36	(1) 2M x 36	(1) 2M x 36
32MB	(1) 2M x 36	(1) 2M x 36	(1) 2M x 36	(1) 2M x 36
32MB	(1) 2M x 36	(1) 2M x 36	(1) 4M x 36	NONE
32MB	(1) 4M x 36	(1) 4M x 36	NONE	NONE
40MB	(1) 1M x 36	(1) 1M x 36	(1) 4M x 36	(1) 4M x 36
48MB	(1) 2M x 36	(1) 2M x 36	(1) 4M x 36	(1) 4M x 36
48MB	(1) 4M x 36	(1) 4M x 36	(1) 4M x 36	NONE
64MB	(1) 4M x 36	(1) 4M x 36	(1) 4M x 36	(1) 4M x 36

CACHE CONFIGURATION
Size	Bank 0	Bank 1	TAG
64KB	(4) 8K x 8	(4) 8K x 8	(1) 32K x 8
128KB	(4) 32K x 8	NONE	(1) 32K x 8
256KB	(4) 32K x 8	(4) 32K x 8	(1) 32K x 8

CACHE JUMPER CONFIGURATION
Size	JP3	JP4
64KB	pins 3 & 5, 4 & 6 closed	Open
128KB	pins 3 & 5, 4 & 6 closed	pins 1 & 3, 2 & 4 closed
256KB	pins 1 & 3, 2 & 4 closed	pins 1 & 2, 3 & 4, 5 & 6 closed

CPU TYPE CONFIGURATION
Type	JP10
80486SX	pins 1 & 3, 2 & 4, 8 & 9 closed
80487SX	pins 3 & 5 closed
80486DX	pins 1 & 3, 4 & 6, 8 & 9 closed
80486DX2	pins 1 & 3, 4 & 6, 8 & 9 closed
Pentium Overdrive	pins 1 & 3, 2 & 4, 7 & 8, 9 & 10 closed

CPU SPEED CONFIGURATION
Speed	JP7
25MHz	pins 1 & 2, 3 & 4 closed
33MHz	pins 3 & 4 closed
40MHz	pins 1 & 2 closed
50iMHz	pins 1 & 2, 3 & 4 closed
50MHz	Open
66iMHz	pins 3 & 4 closed

VESA WAIT STATE CONFIGURATION
Wait states	JP6
0 wait states	pins 4 & 6 closed
1 wait state	pins 2 & 4 closed

BUS SPEED CONFIGURATION
CPU speed	JP6
<= 33MHz	pins 3 & 5 closed
> 33MHz	pins 1 & 3 closed

VRAM CONFIGURATION
Size	Bank 0	Bank 1
512KB	(8) 44256	NONE
1MB	(8) 44256	(8) 44256

VESA VIDEO CONFIGURATION
Setting	JP17
Enabled	pins 1 & 2 closed
Disabled	pins 2 & 3 closed

VIDEO CONFIGURATION (86C08051 ONLY)
Setting	JP17
1NS	pins 10 & 11, 13 & 14 closed
2NS	pins 11 & 12, 13 & 14 closed
3NS	pins 10 & 11, 14 & 15 closed
4NS	pins 11 & 12, 14 & 15 closed

VIDEO FREQUENCY CONFIGURATION
Size	JP17
43Hz	pins 5 & 6, 8 & 9 closed
56Hz	pins 4 & 5, 8 & 9 closed
60Hz	pins 5 & 6, 8 & 9 closed
70Hz	pins 4 & 5, 7 & 8 closed
72Hz	pins 4 & 5, 7 & 8 closed

LRDY DELAY CONFIGURATION
Type	JP1	JP2
None	pins 5 & 6 closed	Open
2 gate	pins 3 & 4 closed	Open
1 CLK	pins 1 & 2 closed	pins 2 & 3 closed
2 CLK	pins 1 & 2 closed	pins 1 & 2 closed

IDE SPEED CONFIGURATION
Speed	JP11
0	pins 3 & 5, 4 & 6 closed
1	pins 1 & 3, 4 & 6 closed
2	pins 3 & 5, 2 & 4 closed
3	pins 1 & 3, 2 & 4 closed