PIC16F1938 Datasheet, PDF (118/452 Pages) Microchip Technology – 28/40/44-Pin Flash-Based, 8-Bit CMOS Microcontrollers

PIC16(L)F1938/9
EXAMPLE 11-4: ERASING ONE ROW OF PROGRAM MEMORY -
; This row erase routine assumes the following:
; 1. A valid address within the erase block is loaded in ADDRH:ADDRL
; 2. ADDRH and ADDRL are located in shared data memory 0x70 - 0x7F (common RAM)
BCF
BANKSEL
MOVF
MOVWF
MOVF
MOVWF
BSF
BCF
BSF
BSF
MOVLW
MOVWF
MOVLW
MOVWF
BSF
NOP
NOP
BCF
BSF
INTCON,GIE
EEADRL
ADDRL,W
EEADRL
ADDRH,W
EEADRH
EECON1,EEPGD
EECON1,CFGS
EECON1,FREE
EECON1,WREN
; Disable ints so required sequences will execute properly
; Load lower 8 bits of erase address boundary
; Load upper 6 bits of erase address boundary
; Point to program memory
; Not configuration space
; Specify an erase operation
; Enable writes
55h
EECON2
0AAh
EECON2
EECON1,WR
; Start of required sequence to initiate erase
; Write 55h
;
; Write AAh
; Set WR bit to begin erase
; Any instructions here are ignored as processor
; halts to begin erase sequence
; Processor will stop here and wait for erase complete.
; after erase processor continues with 3rd instruction
EECON1,WREN
INTCON,GIE
; Disable writes
; Enable interrupts
DS41574A-page 118
Preliminary
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