PIC18F2220/2320/4220/4320
FIGURE 1-1:
PIC18F2220/2320 BLOCK DIAGRAM
Data Bus<8>
PORTA
Data Latch
Table Pointer <2>
inc/dec logic
21
8
8
8
8
RA0/AN0
RA1/AN1
Data RAM
(512 Bytes)
RA2/AN2/VREF-/CVREF
RA3/AN3/VREF+
RA4/T0CKI/C1OUT
RA5/AN4/SS/LVDIN/C2OUT
OSC2/CLKO/RA6(3)
OSC1/CLKI/RA7(3)
21
21
Address Latch
20
PCLATU PCLATH
PCU PCH PCL
12(2)
Address Latch
Program Memory
(4 Kbytes)
Address<12>
Program Counter
4
BSR
12
FSR0
4
PORTB
Data Latch
Bank0, F
RB0/AN12/INT0
RB1/AN10/INT1
RB2/AN8/INT2
RB3/AN9/CCP2(1)
RB4/AN11/KBI0
RB5/KBI1/PGM
RB6/KBI2/PGC
RB7/KBI3/PGD
FSR1
FSR2
31 Level Stack
12
16
inc/dec
logic
Decode
Table Latch
8
ROM Latch
PORTC
RC0/T1OSO/T1CKI
RC1/T1OSI/CCP2(1)
RC2/CCP1/P1A
RC3/SCK/SCL
RC4/SDI/SDA
RC5/SDO
Instruction
Register
8
Instruction
Decode &
Control
RC6/TX/CK
RC7/RX/DT
PRODH PRODL
8 x 8 Multiply
3
8
WREG
8
BIT OP
8
OSC1(3)
OSC2(3)
T1OSI
Power-up
Timer
Internal
Oscillator
Block
8
Oscillator
Start-up Timer
8
INT RC
Oscillator
ALU<8>
Power-on
Reset
PORTE
T1OSO
8
Watchdog
Timer
Precision
Voltage
Reference
RE3(2)
Brown-out
Reset
Low-Voltage
Programming
MCLR(2)
VDD, VSS
Fail-Safe
Clock Monitor
In-Circuit
Debugger
Timer3
(16-bit)
Timer0
(8- or 16-bit)
Timer2
(8-bit)
Timer1
(16-bit)
10-bit A/D
Converter
Master
Synchronous
Serial Port
Addressable
USART
Data EEPROM
(256 Bytes)
CCP1
CCP2
Note 1: Optional multiplexing of CCP2 input/output with RB3 is enabled by selection of the CCPMX2 configuration bit.
2: RE3 is available only when the MCLR Resets are disabled.
3: OSC1, OSC2, CLKI and CLKO are only available in select oscillator modes and when these pins are not being used as digital I/O.
Refer to Section 2.0 “Oscillator Configurations” for additional information.
2003 Microchip Technology Inc.
DS39599C-page 9
MICROCHIP [ MICROCHIP ]
