MICRONICS MOTHERBOARD

80486xx EISA (Full size 09-00173-xx)

This document is for the full-sized (13.3" x 12.025") 80486DX-33, 80486DX2-50, and

80486DX2-66 EISA motherboard. The part number for this board is 09-00173-xx.

It's identifying features are: an LED between expansion slots #5 and #6; eight 32-bit

EISA expansion slots; 4 sockets for SIMMs (four banks).

The EISA Slots are numbered 1, 7, 8, 2, 3, 4, 5, & 6. EISA Slots 7,8 are VESA Slots which

support Bus mastering VESA SCSI controllers only.

EISA slots 1 to 6 support EISA Bus mastering controllers.

The Bus clock speed EISA standard is fixed at 8.3MHz.

+=============================+

+ +

+ MOTHERBOARD SWITCH SETTINGS +

+ +

+ * Default setting +

+=============================+

1 Memory size (see below)

2 Memory size (see below)

3 Memory size (see below)

4 Memory size (see below)

5 Memory size (see below)

6 CPU Speed 33Mhz On / 25Mhz Off

7 CPU Speed 33MHZ Off / 25Mhz Off

8 Color video adapter *On

Mono video adapter Off

DIP switch settings for memory size

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Memory Banks DIP Switch 2

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MB 0 1 2 3 S1 S2 S3 S4 S5

---- ---- ---- ---- ---- ---- ---- ---- ---- ----

1MB 256K ON ON ON ON ON

2MB 256K 256K OFF ON ON ON ON

3MB 256K 256K 256K ON OFF ON ON ON

4MB 256K 256K 256K 256K OFF OFF ON ON ON

4MB 1MB ON ON OFF ON ON

5MB 256K 1MB ON ON OFF OFF ON

6MB 256K 256K 1MB ON OFF ON OFF ON

7MB 256K 256K 256K 1MB OFF ON ON OFF ON

8MB 1MB 1MB OFF ON OFF ON ON

9MB 256K 1MB 1MB ON OFF OFF OFF ON

10MB 256K 256K 1MB 1MB OFF OFF ON OFF ON

12MB 1MB 1MB 1MB ON OFF OFF ON ON

13MB 256K 1MB 1MB 1MB OFF OFF OFF OFF ON

16MB 1MB 1MB 1MB 1MB OFF OFF OFF ON ON

16MB 4MB ON ON OFF ON OFF

20MB 1MB 4MB ON ON OFF OFF OFF

24MB 1MB 1MB 4MB ON OFF ON OFF OFF

28MB 1MB 1MB 1MB 4MB OFF ON ON OFF OFF

32MB 4MB 4MB OFF ON OFF ON OFF

36MB 1MB 4MB 4MB ON OFF OFF OFF OFF

40MB 1MB 1MB 4MB 4MB OFF OFF ON OFF OFF

48MB 4MB 4MB 4MB ON OFF OFF ON OFF

52MB 1MB 4MB 4MB 4MB OFF OFF OFF OFF OFF

64MB 4MB 4MB 4MB 4MB OFF OFF OFF ON OFF

In the table above, 256K indicates that (1) 256Kx36 SIMM is installed in the bank,

1MB indicates that (1) 1Mx36 SIMM is installed in the bank, and 4MB indicates that

4Mx36 SIMM is installed in the bank. The above shows all of the possible memory

configurations.

When installing more than 16MB of memory, BIOS relocation must be disabled. Bios

relocation copies the video Bios (C0000-C7FFF) and the system ROM Bios (F0000-FFFFF) into

RAM. The motherboard adds 15MB to these addresses (F00000) to be able to differentiate

between the ROM and RAM. Enabling the relocation feature causes the memory above 16MB

to become non-contiguous and therefore inaccessible.

Micronics Computers has tested and verified the following memory brands:

Toshiba, Siemens, Mitsubishi, NEC

+=============================+

+ +

+ MOTHERBOARD JUMPER SETTINGS +

+=============================+

J1 Keyboard connector

Pin 1 - Keyboard clock

Pin 2 - Keyboard data

Pin 3 - no connector

Pin 4 - Ground

Pin 5 - +5 volts DC

J17 External 6-volt battery connector

Pin 1 - Battery Positive

Pin 2 - no connector

Pin 3 - Ground

Pin 4 - Ground

J22 External speaker

Pin 1 - Speaker

Pin 2 - no connector

Pin 3 - Ground

Pin 4 - +5 volts DC

J23 Keylock / Power LED

Pin 1 - Power LED signal

Pin 2 - no connector

Pin 3 - Ground

Pin 4 - Keyboard lock signal

Pin 5 - Ground

W5 Reset switch

Pin 1 - Signal

Pin 2 - Ground

W6 Turbo switch

Pin 1 - Signal

Pin 2 - Ground

W7 Turbo LED

Pin 1 - Signal

Pin 2 - Ground

J62 Floppy Controller IRQ 6, DMA CH 2, I/O 3F0-3F7H {AUTO DISABLE}

J30 IDE Interface IRQ 14, I/O 1F0-1F7h {AUTO DISABLE}

W36 IDE Hard Drive LED

1 - Signal

2 - GND

3 - GND

4 - Signal

J63 Serial A 16450 UART IRQ 4 COM 1 or COM3

J64 Serial B 16450 UART IRQ 3 COM 2 or COM4

{ A 16550 UART is present only if the Super I/O Chip is National PC87312 }

J16 Parallel Port connector IRQ 7, @3BCh or @378h

W16 Printer Port mode

Pin 2-3 - Output Mode

Pin 1-2 - Input Mode {scanner}

CPU Clock Speed W54 W55 SW2 #6 SW2 #7

25Mhz ON ON OFF OFF

33Mhz ON OFF ON OFF

PQFP i486SX ZIF Socket W50 W66 W67

Surface Mounted

None i486SX 1-2 2-3 3-4

None i486DX /DX2 2-3 1-2 & 3-4 1-2

i486SX None 1-2 2-3 3-4

i486SX i487SX 1-2 1-2 & 3-4 3-4

i486SX i486DX /DX2 2-3 1-2 & 3-4 1-2

i486SX OverDRIVE 1-2 1-2 & 3-4 2-3

W68 When Local Bus Master Controllers are installed {VL SCSI},

jumper W68 must be placed on Pins 1-2 to support local bus DMA.

Default 2-3

W69 Write protect Flash BIOS programing : W69 - installed

Update Flash BIOS Programming : W69 - open

W65 BIOS Recovery {DO NOT MOVE ! Removing this jumper will erase the BIOS !}

Cache configuration

Direct Mapped Write Through

============================

Cache W20 W21 W52 W44

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64K N/C N/C N/C 2-3

256K 1-2 1-2 1-2 1-2

N/C = Not Connected