In message <30F3D6A7.C814C748@online.ru>, Vassili Zibarov
<rtszib@ONLINE.RU> writes
>Hello
>
>I built a programmer for 16f84 in accordance with Microchip's
>programmins specs. It works fine but there is trouble with BULK ERASE
>and CODE UNPROTECT sequences. They just won't work. Here is how I tried:
>
>Bulk Erase:
>1. Enter Programming Mode
>2. Perform Load all "1" (As I  understood this means "Load Data for
>Programm memory" command 000011 with all "1" in data field  )
>3. Do "Bulk Ease Programm Memory" (thou in programming specs for 16F8X
>item 2.3.1.8 refers as "Bulk Erase Test Memory". I did not find such a
>command in list)
>4. Do "Begin Programming"
>5. Wait 10 ms
>
>I tried this for data memory either - no result.
>
>Also I followed Microchip's recomendations about disabling code protect
>but I could only write the new comfiguration word using their sequence.
>As for disabling code protect also - no result.
>
>If you can help me solve this problem and describe what are the commands
>000001 and 000111?
>Do they require data field or not?
>Please send me right programming sequences or refer to www resources
>where I can get them
>
>Regards
>Vassili Zibarov

If it's any help this is the routine (in Turbo Pascal and Delphi) that I
use to erase a 16x84. I couldn't get it to work either, then someone
told me to add a 'Begin Programming' command before the 'Erase' command,
and that cures the problem.

Const
  {16C84 serial programming commands}

  LdConf = 0;
  LdProg = 2;
  LdData = 3;
  RdProg = 4;
  RdData = 5;
  IncAdd = 6;
  BegPrg = 8;
  ErsPrg = 9;
  ErsDat = 11;

Procedure EraseAll;
Var
  i : Byte;
Begin
  {Clear Protect fuse}
  ProgMode(POn);
  Command(LdConf);
  OutWord($3FFF);
  FOR i := 0 TO 6 Do
    Command(IncAdd);
  Command(1);
  Command(7);
  Command(BegPrg);
  Delay(PgmCfg[Current].Settings[DelayTime]);
  Command(1);
  Command(7);
  Command(BegPrg);
  Delay(PgmCfg[Current].Settings[DelayTime]);
  ProgMode(POff);

  {Clear Data memory}
  ProgMode(POn);
  Command(LdData);
  OutWord($3FFF);
  Command(BegPrg);
  Command(ErsDat);
  Command(BegPrg);
  Delay(PgmCfg[Current].Settings[DelayTime]);
  ProgMode(POff);

  {Clear Program memory}
  ProgMode(POn);
  Command(LdProg);
  OutWord($3FFF);
  Command(BegPrg);
  Command(ErsPrg);
  Command(BegPrg);
  Delay(PgmCfg[Current].Settings[DelayTime]);
  ProgMode(POff);
End;

--

Nigel.

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