PIC16F877-20/P Microchip Technology, PIC16F877-20/P Datasheet - Page 381

• Manufacturer Part Number: PIC16F877-20/P
• Description: IC MCU FLASH 8KX14 EE 40DIP
• Manufacturer: Microchip Technology
• Series: PIC® 16Fr

Specifications of PIC16F877-20/P

• Core Size: 8-Bit
• Program Memory Size: 14KB (8K x 14)
• Core Processor: PIC
• Speed: 20MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 33
• Program Memory Type: FLASH
• Eeprom Size: 256 x 8
• Ram Size: 368 x 8
• Voltage - Supply (vcc/vdd): 4 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: External
• Operating Temperature: 0°C ~ 70°C
• Package / Case: 40-DIP (0.600", 15.24mm)
• Controller Family/series: PIC16F
• No. Of I/o's: 33
• Eeprom Memory Size: 256Byte
• Ram Memory Size: 368Byte
• Cpu Speed: 20MHz
• No. Of Timers: 3
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: 444-1001 - DEMO BOARD FOR PICMICRO MCU
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant

20.12
1997 Microchip Technology Inc.
Initialization
The code in
of the PIC16C62X devices. RA3 and RA4 are configured as digital output. RA0 and RA1 are con-
figured as the V- inputs and RA2 as the V+ input to both comparators.
Example 20-1:
FLAG_REG
;
CLRF
CLRF
ANDLW
IORWF
MOVLW
MOVWF
BSF
MOVLW
MOVWF
BCF
CALL
MOVF
BCF
BSF
BSF
BCF
BSF
BSF
Example 20-1
EQU
FLAG_REG
PORTA
0xC0
FLAG_REG,F
0x03
CMCON
STATUS,RP0
0x07
TRISA
STATUS,RP0
DELAY 10
CMCON,F
PIR1,CMIF
STATUS,RP0
PIE1,CMIE
STATUS,RP0
INTCON,PEIE
INTCON,GIE
Initializing Comparator Module (PIC16C62X)
0X20
depicts example steps required to configure the comparator module
; Init flag register
; Init PORTA
; Mask comparator bits
; Store bits in flag register
; Init comparator mode
; CM<2:0> = 011
; Select Bank1
; Initialize data direction
; Set RA<2:0> as inputs, RA<4:3> as outputs,
;
; Select Bank0
; 10 s delay
; Read
; Clear pending interrupts
; Select Bank1
; Enable comparator interrupts
; Select Bank0
; Enable peripheral interrupts
; Global interrupt enable
Section 20. Comparator
TRISA<7:5> always read ‘0’
CMCON to end change condition
DS31020A-page 20-11
20