Hi Leon, you wrote:-
>Wanting to use the 16C84 EEPROM data memory, I inserted the following
--Snip--
>After running the program, I put the chip into my programmer and read
>the program and EEPROM data memory into the buffers, but the EEPROM data
>has not changed. Can someone please tell me what I am doing wrong?
>
>Leon
>--
>Leon Heller, G1HSM                | "Do not adjust your mind, there is
>E-mail leon@lfheller.demon.co.uk  |  a fault in reality": on a wall
>Phone: +44 (0)1734 471424         |  many years ago in Oxford.

Here is some code taken directly from a working program I wrote. It is
written in Parallax Assembler (PASMX) but you should get the idea.
This is a clip of the list output from the assembler and the first column is
line numbers followed by the assembler code words.
You can see from this which PASMX instructions map to multiple Mchip
instructions.
In the great traddition of these things, the simpler lower level routines
are listed first. (n.b. :loop is a local label)
Sorry I didn't have time to translate it for you. I hope it is of some help.
(Contact me direct if there is anything else you need help with Leon -
remember the transputer and QL? - long time no see!)

All the best.

Dave.

  1060                                  ;Routine to write a byte to the EEPROM,
assumes EEADR and EEDATA have
  1061                                  ;already been loaded with the required
values and EEwrenable has already
  1062                                  ;been called to prime the safety
lockout mechanism.
  1063    031D- 138B                    EEwriteit       clrb    GIE
;must run with interrupts disabled
  1064    031E- 1683                                    setb    RP0
;these registers are in page 1
  1065    031F- 3055 0089                               mov     EECON2,#55h
;Required sequence to
activate write
  1066    0321- 30AA 0089                       mov     EECON2,#0AAh    ;55, AA,
 set WR.
  1067    0323- 1488                                    setb    WR
  1068    0324- 1E08 2B24               :loop           jnb     EEIF,:loop
;wait until write
is complete
  1069    0326- 1108                                    clrb    WREN
;safe once again !
  1070    0327- 1208                                    clrb    EEIF
;reset indicator for next
time.
  1071    0328- 1283                                    clrb    RP0
  1072    0329- 0009                                    reti
;reenable interrupts when all done
  1073
  1074    032A- 1683                    EEread          setb    RP0
;control register is
in Page 1.
  1075    032B- 1408                                    setb    RD
;initiate read operation
  1076    032C- 1283                                    clrb    RP0
  1077    032D- 0008                                    ret
  1078
  1079    032E- 1683                    EEwrenable      setb    RP0
;EEPROM write
enable safety guard
  1080    032F- 1508                                    setb    WREN
  1081    0330- 1283                                    clrb    RP0
  1082    0331- 0008                                    ret
  1083
  1084    0332- 232E                    EEwrite         call    EEwrenable
  1085    0333- 231D                                    call    EEwriteit
  1086    0334- 0008                                    ret
  1087
  1088                                  ;Get EEPROM data into RAM
  1089                                  ;Enter with R1=source, W=destination,
R2=number of bytes to move
  1090    0335- 0084                    EEget           mov     FSR,W
;start addr of target
regs.
  1091    0336- 0826 0089               :loop           mov     EEADR,R1
;point to byte to
retrieve
  1092    0338- 232A                                    call    EEread
;select read mode
  1093    0339- 0808 0080                               mov     INDIRECT,EEDATA
;load
non-volatile value to working reg
  1094    033B- 0A84                                    inc     FSR
;next indirect address
  1095    033C- 0AA6                                    inc     R1
  1096    033D- 0BA7 2B36                       djnz    R2,:loop
  1097    033F- 0008                                    ret
  1098
  1099                                  ;Put RAM data into the EEPROM.
  1100                                  ;Enter with R1=destination, W=sorce,
R2=number of bytes to move.
  1101    0340- 0084                    EEput           mov     FSR,W
  1102    0341- 0826 0089               :loop           mov     EEADR,R1
;point to byte to store
  1103    0343- 0800 0088                               mov     EEDATA,INDIRECT
;load ram value
to EE reg
  1104    0345- 2332                                    call    EEwrite
  1105    0346- 0A84                                    inc     FSR
;next indirect sorce address
  1106    0347- 0AA6                                    inc     R1
;next destination address
  1107    0348- 0BA7 2B41                       djnz    R2,:loop
  1108    034A- 0008                                    ret