PIC18F2450/4450
FIGURE 1-1:
PIC18F2450 (28-PIN) BLOCK DIAGRAM
Data Bus<8>
Table Pointer<21>
inc/dec logic
21
20
PCU PCH PCL
Program Counter
8
PCLATU PCLATH
PORTA
8
Data Latch
Data Memory
(2 Kbytes)
Address Latch
12
Data Address<12>
4
BSR
12
FSR0
FSR1
FSR2
inc/dec
logic
4
Access
Bank
12
PORTB
RB0/AN12/INT0
RB1/AN10/INT1
RB2/AN8/INT2/VMO
RB3/AN9/VPO
RB4/AN11/KBI0
RB5/KBI1/PGM
RB6/KBI2/PGC
RB7/KBI3/PGD
RA0/AN0
RA1/AN1
RA2/AN2/V
REF
-
RA3/AN3/V
REF
+
RA4/T0CKI/RCV
RA5/AN4/HLVDIN
OSC2/CLKO/RA6
31 Level Stack
Address Latch
Program Memory
(24/32 Kbytes)
Data Latch
8
Table Latch
STKPTR
ROM Latch
Instruction Bus <16>
IR
Address
Decode
8
Instruction
Decode &
Control
State Machine
Control Signals
PRODH PRODL
3
OSC1
(2)
OSC2
(2)
T1OSI
T1OSO
MCLR
(1)
V
DD
, V
SS
V
USB
Single-Supply
Programming
In-Circuit
Debugger
Internal
Oscillator
Block
INTRC
Oscillator
Power-up
Timer
Oscillator
Start-up Timer
Power-on
Reset
Watchdog
Timer
Brown-out
Reset
Fail-Safe
Clock Monitor
Band Gap
Reference
BITOP
8
8
ALU<8>
8
8 x 8 Multiply
8
W
8
8
PORTC
RC0/T1OSO/T1CKI
RC1/T1OSI/UOE
RC2/CCP1
RC4/D-/VM
RC5/D+/VP
RC6/TX/CK
RC7/RX/DT
8
USB Voltage
Regulator
PORTE
MCLR/V
PP
/RE3
(1)
BOR
HLVD
Timer0
Timer1
Timer2
ADC
10-bit
CCP1
EUSART
USB
Note 1:
2:
RE3 is multiplexed with MCLR and is only available when the MCLR Resets are disabled.
OSC1/CLKI and OSC2/CLKO are only available in select oscillator modes and when these pins are not being used as digital I/O. Refer
to
for additional information.
DS39760A-page 10
Advance Information
©
2006 Microchip Technology Inc.
MICROCHIP [ MICROCHIP TECHNOLOGY ]
