P89C51RB2HBA NXP Semiconductors, P89C51RB2HBA Datasheet - Page 31

• Manufacturer Part Number: P89C51RB2HBA
• Manufacturer: NXP Semiconductors

Specifications of P89C51RB2HBA

• Cpu Family: 89C
• Device Core: 80C51
• Device Core Size: 8b
• Frequency (max): 33MHz
• Interface Type: UART
• Program Memory Type: Flash
• Program Memory Size: 16KB
• Total Internal Ram Size: 512Byte
• # I/os (max): 32
• Number Of Timers - General Purpose: 3
• Operating Supply Voltage (typ): 5V
• Operating Supply Voltage (max): 5.5V
• Operating Supply Voltage (min): 4.5V
• Instruction Set Architecture: CISC
• Operating Temp Range: 0C to 70C
• Operating Temperature Classification: Commercial
• Mounting: Surface Mount
• Pin Count: 44
• Package Type: PLCC
• Lead Free Status / Rohs Status: Not Compliant

Philips Semiconductors
2002 May 24
80C51 8-bit Flash microcontroller family
16KB/32KB/64KB ISP/IAP Flash with 512B/512B/1KB RAM
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 26. PCA Watchdog Timer Initialization Code
28
P89C51RB2/P89C51RC2/
P89C51RD2Hxx
Product data