Rod Wilson wrote:

> Hi all,
>
> Has anyone on the list built the LUDIPIPO PIC Programmer
> for the 16C84? Does it work?
>
>

Hello Rod

Don't know about Ludipipo.
A few months ago, I asked in this group if a simple in-circuit
programmer
might not be as good as buying  Microchip's programmer.
You will find a reply below.  I built that programmer and had no
problems.  In-circuit programming works without having to disable
the clock (see below).  I recommend it.    You will find the progr.
software at:

http://sistudio.com/sistudio/download.html

If you later want to be able to program _any_ other PIC-procesor, you
might build  Octavio Noguerieras parallell port programmer, which
is much more complicated, but not only programs the whole range,
but also checks programming at different supply voltages, really
necessary only for production programming.  Also for
in-circuit programming, but a disadvantage is that it seems to
be necessary to stop the clock from running by grounding
CLKIN.
Works very nicely under Win95.  It's at:

http://www.geocities.com/SiliconValley/Pines/6902/index.html

Both work well with MPLAB assembler-editor-simulator, that you can
download from www.microchip.com
Check the include files included (!) in MPLAB.
You can specify the config bits like this:

 list p=16c84

#include p16c84.inc

 __config _xt_osc & _wdt_off & _pwrte_on & _cp_off

__________________________________________________________________
clippings from replies by Dennis Frost - I'm sure he won't mind

   Hello Gustaf

Your approach is the best way to go. I have been operating that way for
a
year now. I have several production units running & I program them all
using a simple serial port controlled programmer.
I use the reprogrammable 16F84. This is the easiest chip to use as you
can
erase it in circuit. There is nothing that you can program with the
MicroChip programmer that you cannot program with the many serial
programmers available.

I would suggest that you use a program called PIP02 as a programmer. It
is
dos based but runs under windows. It is faster than other serial
programmers I have used. My actual programmer consists of a serial cable

and 3 resistors!
I got the diagram (that I modified slightly) from Com84.zip. I can't
remember where I got it from, but it is only 16K so I can send it to you
if
you want it. The PIP02 programmer is available from many sites but it
originates from Silicon Studio. There are currently two versions I use.
The
one is v1.04 & the other 1.14. The older version doesnt support the F84.

The newer one does but it has a small bug in it in that it doesn't close

the hex file once it has loaded it. This prevents you from keeping the
programmer running (Under windows) while you are trying to use Mplab to
assemble.

Cheers
        Dennis
___________________________________________________________

Here is a diagram of the changes I made to the Com84 programmer. I have
been using it for a year on a 120 Meg Pentium without problems. (If you
can't make out the circuit then cut it out & paste it into notebook)
I like this programmer because I usually have other things plugged into
my
parallel ports.

Don't give up hope. I started in Pics trying to use a Parallel
programmer
and had all sorts of problems. That's why I now use a serial programmer.

How can you get simpler than 3 resistors?


 Cable to PC's     :       Unit under development
   serial port     :
                   :    +--------+---> 5V from on board PSU
                   :    |        |
                   :    |        |
                   :    /        |
                   :    \10K     |
                   :    /        |
                   :    \        |
                   :    |        |14
                   :    |  +-----------+
                   :    |  |     Vdd   |
                   :    |  |           |
   3   1K     /    :    | 4| ____      |
TXD---/\/\/--o  o--:----+--| MCLR      |-------
            switch :       |           |
                   :       |           |-------
                   :       |  16C84    |
                   :       |    or     |-------
                   :       |  16F84    |
                   :       |           |-------
                   :       |           |
   7   2K2         :     12|           |-------
RTS---/\/\/--------:-------|RB6        |
                   :       |           |
   4   2K2         :     13|           |
DTR---/\/\/--+-----:-------|RB7        |
   8         |     :       |           |
CTS----------+     :       |    Vss    |
                   :       +-----------+
                   :             |5
                   :             |
   5               :             |
GND----------------:-------------+---> 0V from on board PSU
                   :

PIP02 works very well but be careful. V1.14 has some bugs. One is that
the
configuration bits
are not picked up from your hex file correctly and the other is you
cannot
compile in MPLAB (Under windows) if you have PIP02 V1.14 open in another

window. PIP02 doesn't close the hex file so MPLAB cannot access it. This

wasn't the case with the older version.

Cheers

Dennis
_____________________-

.good luck

Gustaf