Hi Wagner,

as I said, I used the USBMOD2 from gigatechnology as an USB module.
It comes as a standard 32-pin DIL package, and contains the FT8U245
and all the circuitry that is needed to make it run, including the
crystal and the USB connector, except the EEPROM; see
www.gigatechnology.com for more details (I have to add, I am not
involved with them other then as a customer). I connected the  data
pins of the FT245 to the PORTC of the 18C442, and the four control
pins to the pins 4-7 of the PORTB. As a clock, I used AEL1210 40MHz
crystal oscillator module. The remaining ports' pins are available
for your own use.

I use it with a Macintosh, and access the USBMOD2/FT245 from inside a
program written in C. The FTDI driver requires no special
installation other then dropping it in the extensions folder. The
driver is automatically loaded when you insert the USB plug, and is
unloaded when you unplug it. The computer treats it as a serial
device (a COM port at higher level); I found no difficulties with
that; my application used a true serial port before, and I had almost
no changes to make. You have to close the "serial" driver correctly
before closing the application or unplug the connector; otherwise,
the USB port remains orphan, and the only way to free it is
restarting the computer. I made no try with a PC; it seems that FTDI
makes available smarter tools for PC anyway.

The PIC code is written with MPLAB, and is, as I said, a small
"operating system" that responds to command codes; it could be easily
modified to simply send and receive data. If you are interested, I
can share the code.

Regards
Leonardo Perretti

--
http://www.piclist.com#nomail Going offline? Don't AutoReply us!
email listserv@mitvma.mit.edu with SET PICList DIGEST in the body