Alan B. Pearce writes:

> At the moment it is the only chip in the PIC line using USB, and Microchip
> have a number of technical notes on using it as a keyboard, mouse and
> joystick interface. However it has a downside in that it is only available
> as OTP plastic package or windowed UV erasable EPROM, so development of code
> is not the easiest unless you have a suitable UV lamp, or large budget to
> buy numbers of OTP chips.

Given the relative cheapness of this chip (I think it's in the
five-buck range) and the fact that it is DIP, it would *seem* that a
"canned" program that provides simple serial and/or parallel I/O would
be a real boon to the entry-level developer.  Sure, it would mean at
least *two* chips in the finished product, but this is far less of a
hassle when you consider the programming involved to get everything
onto one chip and that you wouldn't need to pop for an eprom eraser.
Is anyone aware of code (both on the PC and PIC end) that implements
this?

As an aside, has anyone ever tried to erase an EPROM with an UV led?
Do they even make UV LEDs with a short enough wavelength and enough
power to erase a PIC?  I could imagine a single LED focused directly
onto the chip doing the trick *if* the above conditions are met.
Certainly not an industrial solution, but might be a good hack for the
hobbyist.

> However you may be better off waiting for the new 18F chip announced
> recently which has USB capability. Still download and absorb the information
> in the technical notes for the 16C745 as it will give you a good grounding
> on the USB side of things.

Does anyone have any idea of the release date of the 18F-series USB
chip?  Alternatively, are there any other inexpensive DIP-based
solutions?  I'm aware of the FTDI SIMM-on-DIP developer packages from
Parallax (etc) but they are all in the $30+ range.  Ideally, I'd like
to find a DIP solution in the sub $10 range.

-p.
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