Epson 4DX/33 User Manual

EPSON Equity 4SX/25,4DX/33, and 4DX2/50

Memory

ROM

Video RAM

Shadow RAM

Cache

Math

coprocessor

Clock/calendar

Video

32-bit CPU

 Intel

®

 

 25 MHz

microprocessor; can be replaced with

optional 

 or 

 processor

 Intel 

 33 MHz

microprocessor; can be replaced with

optional 

 

 processor

System speed

 Intel 

 MHz

microprocessor
High and low speeds available; high speed

depends on CPU (25 

 33 MHz, or

50 MHz), low speed is simulated 8 MHz

speed; speed selection through keyboard

command; 0 wait state memory access at

highspeed

Hard disk

Monitor

Parallel

Serial

To select low speed, press the 

 Alt,

and   keys simultaneously. To select

high speed, press the 

   and + keys

simultaneously. (Use the   or + key on the

numeric keypad.)
4MB RAM standard on a SIMM;

expandable using 

 

 or 16MB

 to 32MB (maximum); 

 must

be 

 fast-page mode type with 70ns

(or faster) access speed
128KB system BIOS, video BIOS, and

SETUP code located in EPROM on main

system board
512KB DRAM on main system board,

expandable to 
Supports shadowing of system and video

BIOS ROM into RAM

 of internal cache (built into the

microprocessor)
On 

 and 

 systems, math

coprocessor built into the microprocessor;

optional 487 upgrade available for 

system
Real-time clock, calendar, and CMOS

RAM socketed on main system board with

built-in battery backup

Cirrus

®

 VGA controller on main system

board; provides resolutions up to

1024 x 768
Controller on main system board supports

up to two diskette drives or one diskette

drive and one tape drive
Interface on main system board supports

up to two IDE hard disk drives with

built-in controllers

VGA interface built into main system

board for analog or multifrequency VGA

monitor; 

 D-shell connector

One standard 8-bit parallel, uni- or bi-

directional interface built into main system

board; I/O address selectable through

SETUP; 25-pin, D-shell connector
Two RS-232C, programmable,

asynchronous interfaces built into main

system board; 9-pin, D-shell connectors