Datasheet

 1996 Microchip Technology Inc. DS30412C-page 11
PIC17C4X
FIGURE 3-2: PIC17CR42/42A/43/R43/44 BLOCK DIAGRAM
CLOCK GENERATOR
POWER ON RESET
WATCHDOG TIMER
OSC STARTUP TIMER
TEST MODE SELECT
SYSTEM
DATA LATCH
ADDRESS LATCH
PROGRAM
MEMORY
(EPROM/ROM)
TABLE PTR<16>
STACK 16 x 16
PCH PCL
PCLATH<8>
TABLE LATCH <16>
ROM LATCH <16>
LITERAL
INSTRUCTION
DECODER
CONTROL OUTPUTS
IR LATCH <16>
FSR0
FSR1
8
8
8
IR BUS <16>
RAM ADDR BUFFER
DATA LATCH
READ/WRITE
DECODE
FOR REGISTERS
MAPPED
IN DATA
SPACE
WREG <8>
BITOP
ALU
SHIFTER
IR BUS <16>
PORTB
PORTA
RB0/CAP1 RB1/CAP2 RB2/PWM1 RB2/PWM2 RB4/TCLK12 RB5/TCLK3 RB6 RB7
RA0/INT RA1/T0CKI RA2 RA3 RA4/RX/DT RA5/TX/CK
RA1/
Timer1, Timer2, Timer3
CAPTURE
PWM
DIGITAL I/O
PORTS A, B
SERIAL PORT
Timer0 MODULE
DATA BUS <8>
BSR<7:4>
RA1/T0CKI RA0/INT
86
8
6 2
6
4
3
IR <2:0>
DATA BUS <8>
CONTROL
SIGNALS
TO CPU
CHIP_RESET
AND OTHER
CONTROL
SIGNALS
Q1, Q2, Q3, Q4
16
16
13
AD <15:0>
PORTC and
ALE, WR
, OE
PORTE
OSC1, OSC2
V
DD, VSS
MCLR/VPP
TEST
DECODE
BSR
INTERRUPT
MODULE
12
RDF
WRF
T0CKI
PERIPHERALS
IR <7>
BUS
INTER-
FACE
16
8 x 8 mult
PRODH PRODL
DATA RAM
454 x 8 PIC17C43
8K x 16 - PIC17C44 4K x 16 - PIC17C43
IR BUS<7:0>
4K x 16 - PIC17CR43
454 x 8 PIC17CR43 454 x 8 PIC17C44 232 x 8 PIC17C42A 232 x 8 PIC17CR42
2K x 16 - PIC17C42A 2K x 16 - PIC17CR42
PORTD