Hi All!

I'm trying to modify my PIC programmer to allow programming of PIC16F877.
I'm able to program the code memory, but there are problems with EEPROM
data memory. The memory locations are read as "0", when read just
after programming. (I use the Brian Lane's picprg 2.2 software, modified for
my hardware [see http://www.ise.pw.edu.pl/~wzab/picprog/picprog.html],
and now modified again for 16F877).

The procedure is as follows:
1) The code protection removing (DS39025B - p.10)
   [I assume that this procedure clears also both code and data memories]
2) Programming of the code (in a loop):
        load_code_data (0x2),
        [data],
        begin_programming (0x18),
        read_code_data (0x4),
        increment_address (0x6)
3) Programming of the data (in a loop):
        load_data_data (0x3),
        [data],
        begin_programming (0x18),
        read_data_data (0x5),
        increment_address (0x6),
4) Programming of configuration (DS39025B - p.6)

What am I doing wrong?
--
                              Wojciech M. Zabolotny
        http://www.ise.pw.edu.pl/~wzab  <--> wzab@ise.pw.edu.pl

http://www.debian.org  Linux - free OS for free people!