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LITTLE BOARD/486
AMPRO COMPUTERS, INC.
LITTLE BOARD/486
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Processor
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80486SX/80487SX/80486DX
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Processor Speed
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20/33MHz
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Chip Set
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Ampro
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Max. onboard DRAM
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16MB
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Cache
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32KB optional (location unknown)
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BIOS
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Award
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Dimensions
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330mm x 218mm
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I/O Options
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Floppy drive interface, IDE interface, parallel port, SCSI connector, serial ports (2)
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NPU Options
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None
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CONNECTIONS
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Purpose
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Location
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Purpose
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Location
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Power connector
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J1
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Parallel port
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J6
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Serial port (COM2)
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J2
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SCSI interface
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J7
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Serial port (COM1)
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J3
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Floppy drive interface
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J8
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Utility connector
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J4
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IDE interface
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J11
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Keyboard
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J5
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Power J1-1 to +12V BUS
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W7
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USER CONFIGURABLE SETTINGS
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Function
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Jumper/Switch
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Position
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SCSI controller enabled
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W1
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Closed
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SCSI controller disabled
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W1
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Open
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Factory configured - do not alter
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W3
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N/A
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SCSI controller select IRQ15
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W5
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Open
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SCSI controller select IRQ11
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W5
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Closed
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SCSI termination power enabled
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W6
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Open
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SCSI termination power disabled
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W6
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Closed
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Factory configured - do not alter
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W10
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Closed
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Factory configured - do not alter
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W11
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pins 1 & 2 closed
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Flash EPROM programming power enabled
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W16
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Open
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Flash EPROm programming power disabled
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W16
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Closed
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Watchdog timer select I/O CHCK
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W17
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pins 1 & 2 closed
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Watchdog timer select reset
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W17
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pins 2 & 3 closed
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Watchdog timer disabled
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W17
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Open
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Floppy drive interface enabled
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W18
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Open
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Floppy drive interface disabled
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W18
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Closed
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Floppy precompensation (PCVAL) selection
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W19
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Open
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Floppy precompensation (PCVAL) none
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W19
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Closed
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Floppy drive select IRQ6
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W20 & W27
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Closed
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Floppy drive select IRQ6 disabled
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W20 & W27
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Open
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External cache enabled
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W21
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Open
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External cache disabled
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W21
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Closed
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Factory configured - do not alter
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W22
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N/A
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Power fail NMI enabled
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W23
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Open
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Power fail NMI disabled
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W23
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Closed
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Parallel port interrrupt option select via setup
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W24
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Open
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Parallel port interrrupt option disabled
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W24
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Closed
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Note: W18 may either be an option or is not user configurable.
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DRAM CONFIGURATION
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Size
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Bank 0
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1MB
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(4) 256K x 9
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4MB
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(4) 1M x 9
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16MB
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(4) 4M x 9
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CACHE CONFIGURATION
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Cache
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DRAM
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U9
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U10
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Tag U12
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Tag U13
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32KB
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4MB
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(2) 8K x 8
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(2) 8K x 8
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(2) 8K x 8
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NONE
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32KB
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16MB
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(2) 8K x 8
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(2) 8K x 8
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(2) 8K x 8
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(2) 8K x 8
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EPROM CONFIGURATION (S0)
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EPROM
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W8
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W9
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W25
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27C256
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Open
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pins 7 & 8, 10 & 11
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pins 1 & 2
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27C512
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Open
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pins 1 & 4, 7 & 8, 10 & 11
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pins 1 & 2
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27C010
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Open
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pins 1 & 4, 2 & 5, 6 & 9, 7 & 8
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pins 1 & 2
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27C020
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Open
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pins 1 & 4, 2 & 5, 6 & 9, 7 & 8, 11 & 12
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pins 1 & 2
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27C040
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Open
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pins 1 & 4, 2 & 3, 6 & 9, 7 & 8, 11 & 12
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pins 1 & 2
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27C080
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Closed
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pins 1 & 4, 2 & 3, 7 & 8, 11 & 12
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pins 1 & 2
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62256
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Open
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pins 4 & 7, 5 & 8, 10 & 11
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pins 1 & 2 or 2 & 3
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628128
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Open
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pins 1 & 2, 4 & 7, 5 & 8, 10 & 11
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pins 1 & 2 or 2 & 3
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uPD434000
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Open
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pins 1 & 2, 3 & 6, 4 & 7, 5 & 8, 11 & 12
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pins 1 & 2 or 2 & 3
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28F256
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Open
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pins 2 & 5, 6 & 9, 7 & 8
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pins 1 & 2
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28F512
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Open
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pins 1 & 4, 2 & 5, 6 & 9, 7 & 8
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pins 1 & 2
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28F010
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Open
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pins 1 & 4, 2 & 5, 6 & 9, 7 & 8
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pins 1 & 2
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28F020
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Open
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pins 1 & 4, 2 & 5, 6 & 9, 7 & 8, 11 & 12
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pins 1 & 2
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Note:Pins designated should be in the closed position.
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EPROM/FLASH EPROM CONFIGURATION (S1 & S2)
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EPROM
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W12
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W13
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W14
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W15
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128KB
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pins 2 & 3 closed
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pins 2 & 3 closed
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pins 2 & 3 closed
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pins 2 & 3 closed
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256KB
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pins 2 & 3 closed
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pins 2 & 3 closed
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pins 2 & 3 closed
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pins 2 & 3 closed
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SCSI CONTROLLER CONFIGURATION
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DMA
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W2
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W4
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6
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pins 1 & 2 closed
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Open
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0
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pins 2 & 3 closed
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Closed
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UTILITY CONNECTOR (J4) PIN CONFIGURATION
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Pin
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Signal Name
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Function
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1
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Speaker
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Audio signal
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2
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Speaker
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Ground
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3
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Ground
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To one side of Reset button
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4
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Reset
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To other side of Reset button
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5
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LED Cathode
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Ground return
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6
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LED anode
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Current source (+5v through 330 ohms)
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7
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Ground
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Ground return
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8
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+12V power
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Connected to P1 pin B9
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9
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-5V power
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Connected to P1 pin B5
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10
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-12V power
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Connected to P1 pin B7
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11
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Ground
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Ground return
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12
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POWERGOOD
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Power supply status
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WATCHDOG TIMER CONFIGURATION
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Setting
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W17
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W23
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Disabled
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Open
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Open
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IOCHCK (NMI)
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Pins 1 & 2 closed
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Open
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Reset
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pins 2 & 3 closed
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N/A
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Note:I/O channel check is the bus signal that triggers a non-maskable interrupt (NMI)
Reset is a hard reset signal, the same as pressing the reset button.
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