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EPSON Equity 4SX/25,4DX/33, and 4DX2/50
To select low speed, press the Ctrl, Alt,
hard disk
and - keys simultaneously. To select
access light
(SPEED) light
high speed, press the Ctrl, Alt, and + keys
simultaneously. (Use the - or + key on the
numeric keypad.)
Memory 4MB RAM standard on a SIMM;
expandable using lMB, 4MB, or 16MB
SWIMS to 32MB (maximum); SlMMs must
be 36-bit, fast-page mode type with 70ns
(or faster) access speed
ROM 128KB system BIOS, video BIOS, and
SETUP code located in EPROM o
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EPSON Equity 4SX/25, 4DX/33, and 4DX2/50 Keyboard PS/2 compatible keyboard interface built Video Modes into main system board; num lock setting pode pesolunon 1 colors 1 Memory required 1 selectable through SETUP; 6-pin, mini DIN ~GA p4o~460 connector 640x460 Mouse PS/2 compatible mouse interface built into 640X460 main system board; 6-pin, mini DIN 640x460 connector 600X600 16 Option slots Four 16-bit (or 8-bit) I/O expansion slots, 600x600 256 600X600 ISA compatible, 8 MHz bus speed; three 600
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EPSON Equity 4SX/25,4DX/33, and 4DX2/50 Main System Board Diagram mouse keyboard VGA video parallel serial 2 serial 1 CN2 1 - power supply connectors VGA feature connector standard - 512KB option board CPU chip video riser card < memory connector u21 optional - OverDrive socket (ZIF socket) 512KB 0000000000000000 - - FDD connector 7 1 0000000000000000000 - HDD connector 0000000000000000000 Iii nn 1 ----e-- I” --1 I I I I C CPU I I E (PQFP) I I 0 I I 1 I I U27 I I TOSHIBA I I 0 Ia I I II I I 2
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EPSON Equity 4SX/25, 4DX/33, and 4DX2/50 Serial Port Connectors (CN4 and CN5) Major Subassemblies main system option card connector board board (option board riser card) power supply Serial Port Connector Pin Assignments Keyboard Connector (CN3) and Mouse Connector (CN2) pin 5 pin 6 pin 4 pin 3 i pin 1 ’ SIMM 0 pin 2 SIMM 1 \ diskette speaker drive drive bays Although the keyboard and mouse connectors are physically identical, they cannot be used interchangeably. Keybcmrd and Mouse Connector Pin
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EPSON Equity 4SX/25,4DX/33, and 4DX2/50 VGA Feature Connector (CN8) System I/O Address Map pin 1 040 - Timer, 8254-2 ’ ’ pin 26 8042 (Keyboard and mouse) 070 - Real-time NMI DMA page register, - interrupt controller 2, 8259A VGA Feature Connector Pin Assignments OCO - ODF OF0 Clear math coprocessor busy OF1 Reset math coprocessor OF8 - OFF Math coprocessor Hard disk - 207 IK) - 27F Parallel printer port 2 - (adapter 0) 8 1 1 connected 9 1 1 - 2FF Serial port 2 Prototype card DCA 3278 378
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EPSON Equity 4SX/25, 4DX/33, and 4DX2/50 If the computer’s microprocessor is a FQFP type, it is surface- Jumper Settings mounted on the main system board. To add an OverDrive processor, install it in the empty OverDrive socket and disable the original microprocessor by setting jumper J23 to J7 J5 position 2-3. Also make sure JlO, J11, and J12 are set correctly. Processor Speed Jumper Settirzgs Processor type On Off Off (25 MHz) On (33 MHz) You need to change the processor speed jumper setti
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EPSON Equity 4SX/25, 4DX/33, and 4DX2/50 Hard Disk Drive Types (continued) If the computer has 512KB of video memory, you can install four 256K x 4 bit, 7Ons, 20-pin DRAM DIP (Dual InIine Package) chips to increase the video memory to 1MB. The following table lists which DRAM DIP chips you can install 37 202 683 16 38 rKm 682 CP-3204F on the main system board. 81 548 8 38 rims 547 CP-2084 38 115 761 8 3Q nuls 760 CP-30104 $ 3Q Supported DRAM Chips 40 8-l mo 10 17 PA 70fi0~ MK2024FC II022 15 1 10
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EPSON Equity 4SX/25, 4DX/33, and 4DX2/50 Installing Hard Disk Drives Information Reference List Ll It is recommended that a X-bit, AT-type hard disk controller be used if you are installing a drive that cannot Engineering Change Notices use the embedded IDE interface. If you install a non-IDE None. hard disk drive and controller card, you need to use the SETUP program to disable the built-in IDE hard disk drive Technical Information Bulletins interface. None. 0 When installing a hard disk drive,
