PIC USB Backpack (sorta!) Assembled

Re: PIC USB Backpack (sorta!) Assembled

Reply #15 – September 08, 2011, 09:32:18 pm

This will get the firmware update soon, once the "final" JTR-Honken stack is out.

The backlight display should work with martix orbital already. The contrast I've never tested, but it is a possible 'hack' on the production version by changing the solder jumper.

Re: PIC USB Backpack (sorta!) Assembled

Reply #16 – October 01, 2011, 11:11:46 pm

Hi All,

Way back in May I received a PIC LCD Backpack PCB from Ian. I selected this board in order to start playing with USB connectivity. Due to a heavy travel schedule this summer, and numerous other projects demanding my attention, I just got back to playing with this board a few weeks ago.

Over the years I've built many projects with serial interfaces. A couple of years ago I upgraded a couple of them to USB by tacking a FTDI FT-232R chip on in place of the MAX232. Still, I've always wanted to do it with one of the PIC USB capable chips!

For my first attempt, I decided I'd try to implement a USB temperature and humidity sensor to replicate the one I already have, but without the FTDI chip. I did this by wiring the PIC LCD Backpack to one of my existing boards with only the sensor populated. A picture of the setup is below:

[attachment=1]

Without a lot of difficulty, I was able to get a USB CDC (virtual serial port) version up and running, and reading temperature and humidity. I also wrote a simple Windows program to periodically collect data from my new device, and to test the robustness of the USB connection.

[attachment=0]

I use the CCS 'C' compiler, and frankly I was amazed at how easy it was to get my 18F2550 USB implementation working 100%. I sure wish I tried this a couple of years ago instead of going with the FTDI chips!

I know I didn't use the PCB for the purpose intended, so I'm wondering if I still qualify for another PCB coupon code?

John

Re: PIC USB Backpack (sorta!) Assembled

Reply #17 – October 06, 2011, 02:12:18 pm

Sure you can have a code :) Thanks for sharing your build.