PIC16F84A-04I/SS Microchip Technology, PIC16F84A-04I/SS Datasheet - Page 186

• Manufacturer Part Number: PIC16F84A-04I/SS
• Description: IC MCU FLASH 1KX14 EE 20SSOP
• Manufacturer: Microchip Technology
• Series: PIC® 16Fr

Specifications of PIC16F84A-04I/SS

• Core Size: 8-Bit
• Program Memory Size: 1.75KB (1K x 14)
• Core Processor: PIC
• Speed: 4MHz
• Peripherals: POR, WDT
• Number Of I /o: 13
• Program Memory Type: FLASH
• Eeprom Size: 64 x 8
• Ram Size: 68 x 8
• Voltage - Supply (vcc/vdd): 4 V ~ 5.5 V
• Oscillator Type: External
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 20-SSOP
• Controller Family/series: PIC16F
• No. Of I/o's: 13
• Eeprom Memory Size: 64Byte
• Ram Memory Size: 68Byte
• Cpu Speed: 4MHz
• No. Of Timers: 1
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: XLT20SS1-1 - SOCKET TRANSITION 20DIP 20SSOPI3-DB16F84A - BOARD DAUGHTER ICEPIC3AC164307 - MODULE SKT FOR PM3 28SSOPAC164018 - MODULE SKT PROMATEII 20SSOP
• Data Converters: -
• Connectivity: -
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant
• Other names: PIC16F84A-04I/SSR; PIC16F84A-04I/SSR

PICmicro MID-RANGE MCU FAMILY
DS31012A-page 12-6
Example 12-2
in
Example 12-2:
Writing a 16-bit value to the 16-bit TMR1 register is straight forward. First the TMR1L register is
cleared to ensure that there are many Timer1 clock/oscillator cycles before there is a rollover into
the TMR1H register. The TMR1H register is then loaded, and finally the TMR1L register is loaded.
Example 12-3
Example 12-3:
; All interrupts are disabled
;
; TMR1L may have rolled over between the read of the high and low bytes.
; Reading the high and low bytes now will read a good value.
;
; Re-enable the Interrupt (if required)
CONTINUE
; All interrupts are disabled
; Re-enable the Interrupt (if required)
CONTINUE
Example
MOVF
MOVWF
MOVF
MOVWF
MOVF
SUBWF
BTFSC
GOTO
MOVF
MOVWF
MOVF
MOVWF
CLRF
MOVLW
MOVWF
MOVLW
MOVWF
12-1. This is useful if the timer cannot be stopped.
shows a routine to read the 16-bit timer value with experiencing the issues shown
shows this:
TMR1H, W
TMPH
TMR1L, W
TMPL
TMR1H, W
TMPH,
STATUS,Z
CONTINUE
TMR1H, W
TMPH
TMR1L, W
TMPL
TMR1L
HI_BYTE
TMR1H, F
LO_BYTE
TMR1H, F
Reading a 16-bit Free-Running Timer
Writing a 16-bit Free Running Timer
W
; Read high byte
;
; Read low byte
;
; Read high byte
; Sub 1st read with 2nd read
; Is result = 0
; Good 16-bit read
; Read high byte
;
; Read low byte
;
; Continue with your code
; Clear Low byte, Ensures no
;
; Value to load into TMR1H
; Write High byte
; Value to load into TMR1L
; Write Low byte
; Continue with your code
rollover into TMR1H
1997 Microchip Technology Inc.