Functional Block Diagram; System Bios - NEC Versa 2500 Series Service Manual

3-2 Hardware Functional Overview

FUNCTIONAL BLOCK DIAGRAM

The following figure shows the NEC Versa 2500 Series functional diagram.
Bank 0
8MB
(on-board)
Bank 1
8, 16MB
(DIMM)
Cache RAM
L2: 256 KB
write back
Pentium
P54CSLM-
133MHz
LLM
I N V E R T E R
14.318MHz X'TAL

SYSTEM BIOS

The primary function of the system BIOS (Basic Input-Output System) is to provide a se-
ries of software interrupts, functions, and sub-functions that control operations on certain
devices, such as the hard disk drive, the floppy drive, and the video subsystem.
FLASH BIOS
256KB
C O R E C H I P
U M C
UM8891BF-N,
C O N T R O L L E R
UM8892BF-N,
MITSUBISHI
U M 8 8 8 6 B F - N
VGA CHIP VIDEO RAM
C&T 65548 1MB
C R T O N
66MHz
C L O C K G E N
24MHz
ICS
14.318MHz
AV9154-43
Figure 3-1 Functional Block Diagram
C A R D 0
PCMCIA
O M E G A
82C094
C A R D 1
GLIDE PAD
K B
EXT. KB/MOUSE
M38813M4
INTERNAL KB
SUPER I/O
NS PC87336VLJ
AC or DC
A D A P T E R
C O N V E R T E R
Battery IN
B A T T E R Y I N
C O M 1
P R I N T E R
H D D
F D D
+3.45V
+5V
D C / D C
+12V