>
> > I was wondering if anyone had gotten around to writing a Wloader cloner
> that'll
> > spawn wloader from one chip to another. With low voltage programming it
> should
> > be nothing more than implementing the regular serial programming algorithm
> > for the 16F87X series coupled with a read of WLoader from it's location.
>
> When you want to make it a single-purpose tool it should not be that
> difficult. But personally I would choose not to use the low-voltage
> programming because it can be a nuisance and you can only be sure that it is
> enabled for new chips.

Wouter I'm planning on using this only for new chips. Once they have WLoader
loaded into them, there's no need to ever reprogram them with a "regular"
programmer. In fact I plan to disable low voltage programming once WLoader
is loaded so that RB3 can be recovered.

> Look at the source and hardware for my WISP
> programmer, as you say you could simply put the WLoader code high in the
> F877, the WISP code in the low, make sure the WLoader code is never enabled,
> and add a start-programming button and a programming-finished good/bad LED
> (there are plenty of pins), ignore (leave out) the variable-vcc parts and
> you have you gizmo... Don't forget to set up a web page for it!

OK I sort of see your game plan, but at first glance it seems like bringing
in a slegdehammer to swat a fly. Wisp is a full featured programmer while I
want (as you pointed out above) a single purpose tool. My rationale somewhat
follows yours. The gpasm/gpsim/linwload/wloader combo gives me a rapid
development environment that's ultra transportable because all it requires is
an available serial port to use. And like you I have a bunch of of
16F87X parts and can certainly spare one for single use. But I find this the
killer app because all I ever need to clone a WLoaded 16F87X is any
16F87X with WLoader on it. Simply:

1) Download the cloner to the existing 16F87X.
2) Hook the pristine 16F87X to the existing 16F87X via the standard 5 wire
   serial interface.
3) Fire up the system and clone WLoader.

Now at this point I have 2 Wloaded 16F87X, both which can be used for anything
and at any future point in time can be used to clone other 16F87X parts with
Wloader. (Mental note: augment linwload so that the current program in a
Wloaded 16F87X can be downloaded and saved in a hex file)

In short I can completely ditch my standard PIC programmer because I can use
any Wloaded PIC to clone.

To me this is the killer app. Build an ad-hoc pic programmer out of a handful
of resistors and diodes that can be had at any RatShack and can by put together
in about 10 minutes. BTW it took me a 1/2 day to figure out that the WLoader
uses a non-inverting serial interface which I certainly will build the next
time. My prototype uses a MAX232 and a handful of inverters.

Every PIC programmer that I've ever had, or ever built has been unstable,
requiring either specialized or modified software, a hefty bit of hardware,
or something not easily available to make it go. WLoader, RomZAP, and the
other boot loaders gives me a much simpler tool to work with because the
intelligence is embedded into the target, which in my opinion it should be.

But right now I have one WLoaded chip and 7 blanks. Guess which one I using?

Thanks for all the help. I'll let you know how it turns out.

BAJ

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