gnupic: DIY USB programmer ?
Subject:
DIY USB programmer ?
From:
Manuel Bessler ####@####.####
Date:
4 Jan 2005 17:47:42 +0000
Message-Id: <20050104183941.A19386@betazed3.varxec.de>
Hi all,
I'm looking for a simple DIY design for a USB-based PIC programmer.
(ok that part is easy)
... BUT ... if at all possible such a burner should not require a PIC
itself. (the chicken and egg problem :( )
I have a PIC based Project (called the PIC HomeCockpit Controller, PHCC.
Its for the flightsim people who want to build a cockpit at home).
Now, most folks who build PHCC don't have a PIC programmer at home, so
they need to buy or build one. Of course, the cheaper the better.
But due to the demise of parallel port and serial port, the common types
(JDM, Tait, BAJ) can't be used.
Most new computers only have USB, but no "legacy ports".
I've been wondering if it is possible to build a programmer based on the
FTDI FT232BM or FT245BM chips.
The problem here is the timing. USB can't guarantee the timings as far
as I understand.
I've skimmed the programming specs for two chips, and it looked like
most timings don't have a "max" defined. So, would this be possible ?
What do you guys think ? Could it be possible to build a simple burner
that does not need "intelligence" apart from an USB interface chip.
I know the FTDI USB chips have a "bit-bang mode".
Your opinions please :)
Thanks,
Manuel
--
Opensource/Free Software: No Gates, No Windows
