16F628 on-chip eeprom problem | Piclist

Hi, I even made some assembler-macro's that can be used for the '628. They work perfectly. Kees. ;========================================================================================= ; EEprom macros for PIC 16F628 ;========================================================================================= EEPROM_READ MACRO CONFIG_ADDR BSF STATUS, RP0 ; Bank1 MOVLW CONFIG_ADDR ; MOVWF EEADR ; Address to read BSF EECON1, RD ; perform EEPROM read MOVF EEDATA, W ; store the data BCF STATUS, RP0 ; Bank0 ENDM EEPROM_WRITE MACRO CONFIG_ADDR, CONFIG_DATA BSF STATUS, RP0 ; Bank1 MOVLW CONFIG_ADDR ; MOVWF EEADR ; Address to write MOVLW CONFIG_DATA ; MOVWF EEDATA ; Data to write BSF EECON1, WREN ; Enable Write BCF INTCON, GIE ; Disable Interrupts MOVLW 0x55 ; Write 0x55 MOVWF EECON2 ; MOVLW 0xAA ; Write 0xAA MOVWF EECON2 ; BSF EECON1, WR ; set WR bit BTFSC EECON1, WR ; still set? GOTO $-1 ; wait until cleared BCF EECON1, WREN ; Disable further Writes BSF INTCON, GIE ; Enable Interrupts BCF STATUS, RP0 ; Bank0 ENDM EEPROM_VERIFY MACRO BSF STATUS, RP0 ; Bank1 MOVF EEDATA, W ; last written value in 'W' BSF EECON1, RD ; start read at current address SUBWF EEDATA, W ; subtract W from EEDATA BTFSS STATUS, Z ; ZERO flag set? GOTO write_error ; No, there was a write-error BCF STATUS, RP0 ; Bank0 ENDM --- rj_satterlee <> wrote: > Hi Validmer- > > Well, it's a little more complicated than that. > I've included the > read and write routines to the eeprom memory that I > use for the > 16F628, which I got from the manual. It's assembly, > but I think > that it gives a pretty clear indication of the > process. Seems > to work well for me. > > Hope this helps. > > Cheers, > > Rich S. > > aka WB6VAL > > --- In , "Vladimir M Skrbic" > <atomski@E...> > wrote: > > Hello everyone, > > > > I'm new to the group and I'd like to ask a > question. I've recently > > moved all my projects from 16F84 to 16F628 mcu's. > Yesterday I've > > tried to write data to the internal (on-chip) > eeprom of 16F628 using > > PicBasic Pro with little (or no ;) sucess. Would > anyone care to > > explain why the same code works on 16F84 and > 16F876/877 but not on > > 16F628? I used the most common method: > > > > EEPROM 0, 127 ' Store 127 into eeprom > location 0 > > ... > > [code] > > ... > > READ 0, W ' Put contents of memory > location 0 into W > > ... > > [code] > > ... > > WRITE 0, W ' Put contents in W into eeprom > location 0 > > ... > > END > > > > And neither of the commands work! I've tried all > locations from > > 0 - 11 for example and no luck. What am I doing > wrong? Any help is > > appreciated! Thanks in advance. > > > > -- > > Sincerest regards, > > YZ7REA Vladimir M Skrbic > > 4N7ATV Repeater Administrator > > YU7GHZ Radio Club President ;--------------------------------------------------------------------- > > ; Read Eprom routine > ; inputs: eprom_addr contains the address of the > eprom memory to read > ; outputs: eprom_data contains the data read from > the eprom > ;--------------------------------------------------------------------- > read_eprom > movf eprom_addr, W ;get the address > bsf STATUS, RP0 ;select bank 1 > movwf EEADR ;set address to read > bsf EECON1, RD ;read the eprom > movf EEDATA, W ;hold in w register > bcf STATUS, RP0 ;select bank 0 > movwf eprom_data ;save the information > return ;--------------------------------------------------------------------- > ; Write/verify Eprom routine > ; inputs: eprom_addr contains the address of the > eprom memory to read > ; eprom_data contains the data to write to > the eprom > ; output: W = 0 ==> o.k., W <> 0 ==> error in write > ; uses: eprom_intcon. Stores the state of the > interrupt bit > ; NOTE: this routine COULD hang if the eprom logic > in the hardware > ; fails to operate. Could put a check in for > it. The max > ; time for a byte to be programmed is 8 ms. > ;--------------------------------------------------------------------- > write_eprom > bcf PIR1, EEIF ;clear eprom write int flag > movf eprom_addr, W ;get the address > bsf STATUS, RP0 ;select bank 1 > movf INTCON, W ;get interrupt control > bcf STATUS, RP0 ;select bank 0 > movwf eprom_intcon ;save GIE state > movf eprom_addr, W ;get the address > bsf STATUS, RP0 ;select bank 1 again > movwf EEADR ;set address > bcf STATUS, RP0 ;select bank 0 > movf eprom_data, W ;get the data > bsf STATUS, RP0 ;select bank 1 again > movwf EEDATA ;set the data bits > bsf EECON1, WREN ;set the write enable > bcf INTCON, GIE ;turn off interrupts > movlw h'55' > movwf EECON2 ;first set of eprom write > movlw h'aa' > movwf EECON2 ;second set of eprom write > bsf EECON1, WR ;set the write bit (acutal > write) > bcf STATUS, RP0 ;select bank 0 > ; spin waiting for the write to complete > movlw h'ff' > write_eprom1 > btfss PIR1, EEIF ;test for write complete > goto write_eprom1 ;branch if not finished > ; finished the write > ; now verify write > movf EEDATA, W > bsf EECON1, RD ;read data written > ; value in W == data read? > subwf EEDATA, W > bcf STATUS, RP0 ;select bank 0 > ; reset the interrupt control bit to original value > btfsc eprom_intcon, GIE ;branch if not enabled > bsf INTCON,GIE ;enable general interrupts > return ;if bad w <> 0 __________________________________

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Discussion Groups | Piclist | 16F628 on-chip eeprom problem

16F628 on-chip eeprom problem - Vladimir M Skrbic - Mar 1 16:06:00 2004

Re: Re: 16F628 on-chip eeprom problem - Kees Stenekes - Mar 3 10:32:00 2004