P87C51RB2 PHILIPS [NXP Semiconductors], P87C51RB2 Datasheet - Page 40

• Manufacturer Part Number: P87C51RB2
• Description: 80C51 8-bit microcontroller family
• Manufacturer: PHILIPS [NXP Semiconductors]

Philips Semiconductors
2003 Jan 24
80C51 8-bit microcontroller family
with 512B/1KB RAM, low voltage (2.7 to 5.5 V), low power, high
speed (30/33 MHz)
INIT_WATCHDOG:
;
;********************************************************************
;
; Main program goes here, but CALL WATCHDOG periodically.
;
;********************************************************************
;
WATCHDOG:
MOV CCAPM4, #4CH
MOV CCAP4L, #0FFH
MOV CCAP4H, #0FFH
ORL CMOD, #40H
CLR EA
MOV CCAP4L, #00
MOV CCAP4H, CH
SETB EA
RET
; Module 4 in compare mode
; Write to low byte first
; Before PCA timer counts up to
; FFFF Hex, these compare values
; must be changed
; Set the WDTE bit to enable the
; Hold off interrupts
; Next compare value is within
; 255 counts of the current PCA
; timer value
; watchdog timer without changing
; the other bits in CMOD
Figure 31. PCA Watchdog Timer Initialization Code
8KB/16KB/32KB/64KB OTP
40
P87C51RA2/RB2/RC2/RD2
Product data