PIC18F2431-I/SP Microchip Technology Inc., PIC18F2431-I/SP Datasheet - Page 143

• Manufacturer Part Number: PIC18F2431-I/SP
• Description: Microcontroller; 16 KB Flash; 768 RAM; 256 EEPROM; 24 I/O; 28-Pin-SPDIP
• Manufacturer: Microchip Technology Inc.

Specifications of PIC18F2431-I/SP

• A/d Inputs: 5-Channel, 10-Bit
• Cpu Speed: 10 MIPS
• Eeprom Memory: 256 Bytes
• Input Output: 24
• Interface: I2C/SPI/USART
• Memory Type: Flash
• Number Of Bits: 8
• Package Type: 28-pin SPDIP
• Programmable Memory: 16K Bytes
• Ram Size: 768 Bytes
• Speed: 40 MHz
• Timers: 1-8-bit, 3-16-bit
• Voltage, Range: 2-5.5 V
• Lead Free Status / Rohs Status: RoHS Compliant part Electrostatic Device

EXAMPLE 12-1:
TABLE 12-2:
 2003 Microchip Technology Inc.
INTCON
PIR1
PIE1
IPR1
TMR1L
TMR1H
T1CON
Legend:
RTCinit
RTCisr
Name
Holding Register for the Least Significant Byte of the 16-bit TMR1 Register
Holding Register for the Most Significant Byte of the 16-bit TMR1 Register
x = unknown, u = unchanged, – = unimplemented, read as ‘0’. Shaded cells are not used by the Timer1 module.
GIE/GIEH PEIE/GIEL
RD16
Bit 7
—
—
—
MOVLW
MOVWF
CLRF
MOVLW
MOVWF
CLRF
CLRF
MOVLW
MOVWF
BSF
RETURN
BSF
BCF
INCF
MOVLW
CPFSGT secs
RETURN
CLRF
INCF
MOVLW
CPFSGT mins
RETURN
CLRF
INCF
MOVLW
CPFSGT hours
RETURN
MOVLW
MOVWF
RETURN
REGISTERS ASSOCIATED WITH TIMER1 AS A TIMER/COUNTER
IMPLEMENTING A REAL-TIME CLOCK USING A TIMER1 INTERRUPT SERVICE
T1RUN
ADIE
ADIP
ADIF
Bit 6
0x80
TMR1H
TMR1L
b’00001111’
T1OSC
secs
mins
.12
hours
PIE1, TMR1IE
TMR1H, 7
PIR1, TMR1IF
secs, F
.59
secs
mins, F
.59
mins
hours, F
.23
.01
hours
T1CKPS1 T1CKPS0 T1OSCEN T1SYNC TMR1CS TMR1ON 0000 0000 u0uu uuuu
TMR0IE
RCIE
RCIP
RCIF
Bit 5
; Preload TMR1 register pair
; for 1 second overflow
; Configure for external clock,
; Asynchronous operation, external oscillator
; Initialize timekeeping registers
;
; Enable Timer1 interrupt
; Preload for 1 sec overflow
; Clear interrupt flag
; Increment seconds
; 60 seconds elapsed?
; No, done
; Clear seconds
; Increment minutes
; 60 minutes elapsed?
; No, done
; clear minutes
; Increment hours
; 24 hours elapsed?
; No, done
; Reset hours to 1
; Done
INT0IE
Bit 4
TXIF
TXIE
TXIP
PIC18F2331/2431/4331/4431
Preliminary
SSPIF
SSPIE
SSPIP
RBIE
Bit 3
TMR0IF
CCP1IF
CCP1IE
CCP1IP
Bit 2
TMR2IF
TMR2IE
TMR2IP
INT0IF
Bit 1
TMR1IE
TMR1IP
TMR1IF
Bit 0
RBIF
-000 000x 0000 000u
-000 0000 -000 0000
-000 0000 -000 0000
1111 1111 -111 1111
xxxx xxxx uuuu uuuu
xxxx xxxx uuuu uuuu
POR, BOR
Value on
DS39616B-page 141
Value on
all other
Resets