Post by thread:Writing PIC16C84 EEPROM data memory not working.

Hello, Many thanks to everyone that answered my previous query. My program seems to be going along quite nicely so far but now I've hit a brick wall called DATA EEPROM MEMORY. I just cant seem to write to it! This is what i have currently in the program and im still running it in the simulation. The eeprom Window doesnt update with the new value. Is there something im doing wrong here? -------------------------------------------------- BCF STATUS, RP0 ;Bank 0 ;set eeprom address movf address, W movwf EEADR ;write data to EEDATA movf data1, W movwf EEDATA BSF STATUS, RP0 ;Bank 1 BCF INTCON, GIE ;Disable INT's movlw 0x55 movwf EECON2 ;Write 55h movlw 0xAA movwf EECON2 ;Write AAh bsf EECON1, WR ;Set WR bit begin write bsf INTCON, GIE -------------------------------------------------- Thanks again, Gabes. ____________________________________________________________________ Get free e-mail and a permanent address at http://www.netaddress.com/?N=1

Gabes: {Quote hidden}>My program seems to be going along quite nicely so far but now I've hit a brick > wall called DATA EEPROM MEMORY. I just cant seem to write to it! > >This is what i have currently in the program and im still running it in the > simulation. The eeprom Window doesnt update with the new value. Is there > something im doing wrong here? > >-------------------------------------------------- > BCF STATUS, RP0 ;Bank 0 > ;set eeprom address > movf address, W > movwf EEADR > > ;write data to EEDATA > movf data1, W > movwf EEDATA > > BSF STATUS, RP0 ;Bank 1 > BCF INTCON, GIE ;Disable INT's > movlw 0x55 > movwf EECON2 ;Write 55h > movlw 0xAA > movwf EECON2 ;Write AAh > bsf EECON1, WR ;Set WR bit begin write > bsf INTCON, GIE >-------------------------------------------------- You forgot the "BSF EECON1, WREN ; Enable Write" line -- Lauri --- <a href="http://www.ee.oulu.fi/~lapi/">For more info.</a>

On Sun, 19 Apr 1998 23:39:28 -0400 MARVIN ANDROID <spam_OUTm.androidTakeThisOuTUSA.NET> writes: >Hello, > >Many thanks to everyone that answered my previous query. > >My program seems to be going along quite nicely so far but now I've >hit a brick > wall called DATA EEPROM MEMORY. I just cant seem to write to it! The code attached looks close to right but you have to set the WREN bit in EECON1 at some point before the "required sequence" (maybe even in another routine, gives better protection against unintentional writes). Simply clearing the GIE bit isn't certain to disable interrupts. Also it's a good idea to check/poll the WR bit before or after writing to be sure the EEPROM isn't still busy with the last write. Has anyone done a definite test to see if the EEPROM can be read while it's writing? The only place Microchip ever claimed that was in the "Truth about AVR" and of course that wasn't all true. _____________________________________________________________________ You don't need to buy Internet access to use free Internet e-mail. Get completely free e-mail from Juno at http://www.juno.com Or call Juno at (800) 654-JUNO [654-5866]