PIC16F84A-20/SS Microchip Technology, PIC16F84A-20/SS Datasheet - Page 110

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

Specifications of PIC16F84A-20/SS

• Core Size: 8-Bit
• Program Memory Size: 1.75KB (1K x 14)
• Core Processor: PIC
• Speed: 20MHz
• 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: 0°C ~ 70°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: 20MHz
• 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

PICmicro MID-RANGE MCU FAMILY
6.5
DS31006A-page 6-16
Design Tips
Question 1:
Answer 1:
When a device with more then 2K words of program memory is used, the calling of subroutines
may require that the PCLATH register be loaded prior to the CALL (or GOTO) instruction to specify
the correct program memory page that the routine is located on. The following instructions will
correctly load PCLATH register, regardless of the program memory location of the label SUB_1.
SUB_1
Question 2:
Answer 2:
Example 6-4
of the code may be removed.
MOVLW
MOVWF
CALL
:
:
:
:
RETURN
shows this. If the device you are using does not use all 4 data memory banks, some
Program execution seems to get lost.
I need to initialize RAM to ’0’s. What is an easy way to do that?
HIGH (SUB_1)
PCLATH
SUB_1
; Select Program Memory Page of
;
; Call the desired routine
; Start of routine
; Return from routine
Routine.
1997 Microchip Technology Inc.