EPSON Endeavor 486C

System Memory Map

23FFFFF

 

36MB

Hard Disk Drive Jumper Settings

•lf CS (cable selection) is jumpered, the drive is a master if pin-28 is grounded and a slave if pin-28 Is not grounded.

DIP Switch Settings

Extended memory

0100000 I

 

1MB

 

System BIOS

 

(Shadow RAM, 64KB)

Switch

Setting

1**

ON

 

OFF

2**

ON

 

O f f

3**

ON

 

O f f

4

ON’

 

O f f

5

ON’

 

O f f

33 MHz CPU speed

25 MHz CPU speed

25 MHz CPU speed

33 MHz CPU speed

CPU present in PGA socket CPU absent from PGA socket

Enable password security feature Disable password security feature

Select color monitor

Select monochrome monitor

OOFOOOO

 

 

 

Reserved for system BIOS (64KB)

 

 

 

 

 

00E0000

 

 

 

Reserved for ROM on l/O cards

 

 

 

 

 

00C7FFF

 

 

 

VGA BIOS ROM (Shadow, 32KB)

 

 

 

 

 

 

 

 

 

 

VGA Color Text

 

 

00B8000

 

 

 

VGA Mono Text

 

 

 

 

 

00B0000

 

 

 

VGA Graphics

 

 

 

 

 

00A0000

 

 

640KB

Base memory

 

 

 

 

 

 

 

 

Jumper and DIP Switch Settings

Display Adapter and CPU Jumper Settings

Jumper

 

Setting

 

Function

J3

 

A*

 

Enable the built-in VGA adapter

 

 

B

 

Disable the built-in VGA adapter so you can use a

 

 

 

 

display adapter on an option card as your primary 1

 

 

 

 

adapter

J4

 

A**

 

Select DX or DX2 CPU

 

 

B

 

Select SX CPU

* Factory

setting

• * Factory set according to system CPU

External Cache Jumper Settings

*Factory setting; change jumpers only if external cache chips am Installed

* Factory setting • * Factory set according to system type

Processor Chips

The 4SX/25C or 4DX/33C systems can be upgraded with an Intel OverDrive processor on the main system board to effectively double the internal clock speed of the computer’s microprocessor. Alternatively, the 4SX/25C accepts the Intel 487SX/25 microprocessor with built-in math coprocessor.

OverDrive Processors

OverDrive processor

ODP486-25

ODP486-33

SIMM Installation

The computer comes with 4MB of memory on the main system board. To increase the amount of memory in the computer up to 36MB, install 36-bit, fast-page mode SIMMs that operate at an access speed of 70ns or faster, with a capacity of 1MB, 4MB, or 16MB.

The following table shows the possible SIMM configurations; do not install memory in any other configuration.

SIMM Configurations

•Standard memory on the system board ** SIMMs can occupy either socket

EPSON Endeavor 486C-6

7/15/93