3-2 Hardware Functional Overview
FUNCTIONAL BLOCK DIAGRAM
The following figure shows the NEC Versa 2500 Series functional diagram.
Bank 0
8 M B
(on-board)
Bank 1
8, 16MB
(DIMM)
C a c h e R A M
L2: 256 KB
write back
C O R E C H I P
U M C
UM8891BF-N,
U M 8 8 9 2 B F - N ,
U M 8 8 8 6 B F - N
V G A C H I P
C & T 6 5 5 4 8
C R T O N
L L M
I N V E R T E R
F L A S H B I O S
2 5 6 K B
P C M C I A
O M E G A
8 2 C 0 9 4
K B
C O N T R O L L E R
MITSUBISHI
M 3 8 8 1 3 M 4
SUPER I/O
N S P C 8 7 3 3 6 V L J
G L I D E P A D
E X T . K B / M O U S E
I N T E R N A L K B
C A R D 1
C A R D 0
F D D
H D D
P R I N T E R
C L O C K G E N
ICS
AV9154-43
AC or DC
A D A P T E R
D C / D C
C O N V E R T E R
2 4 M H z
14.318MHz X'TAL
B A T T E R Y I N
V I D E O R A M
1 M B
C O M 1
Battery IN
+3.45V
+ 5 V
+ 1 2 V
6 6 M H z
14.318MHz
P e n t i u m
P 5 4 C S L M -
1 3 3 M H z
Figure 3-1 Functional Block Diagram
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.
