Thread: HU Quality AM/FM RDS/RBDS Radio with Features

Originally Posted by Chris31

Go for the 16F because they are much cheaper.

True but there aren't any 16F parts with USB hardware, only OTP. So we could have saved a few bucks on a cheaper 16F but then add it right back for the FTDI and supporting chips, larger layout, etc. The 18F looked to be a cleaner and ultimately cheaper solution. It's a fairly powerful beast and since it's flashable, it leaves open the possibilitiy of extending the radio to possibly do other things of interest to the community (relay control, temperature sensing, dead reckoning, ...).

Originally Posted by Dexter

yea bit bang the I2C

Right, and if you're going to bit bang, you might as well just ditch the PIC all together. You can bit bang directly from the PC serial (+ level converter) or parallel port.

Originally Posted by Dexter

Sorry
Gotcha now. I thought the cost of the 18 family was really high compared to a 16 and some extra components but i havent really checked it out lately. sorry again. If you want my 18 chip you can have it, i have no use for it.

The 18F2455 is listed at ~$9/ea at Digikey for single unit quantities but drops to $5/ea for purchsees of 25. That's why we're thinking about doing kits to keep the cost down.

Originally Posted by Dexter

Sorry
Gotcha now. I thought the cost of the 18 family was really high compared to a 16 and some extra components but i havent really checked it out lately. sorry again. If you want my 18 chip you can have it, i have no use for it.

No apologies needed ... we're open to discussing ideas.

The 18F2455 is listed at ~$9/ea at Digikey for single unit quantities but drop quickly to $5/ea for purchsees of 25. That's why we're thinking about doing kits to keep the cost down.

Hold on to the 18F. You might be able to use it to assemble one of these boards.

Hi,

I'm back from a week of snowboarding and ready to kick ... again.

First of all some info about the features of the prototype:

AM/FM car tuner module
RDS/RBDS
USB controlled
Serial output (without MAX232), example for use with small LCD with RDS info
I²C output, to connect other I²C devices and control them through USB.
Phone input (with activation input to switch the sound processor)
AUX input
4 channel output (LF-RF, LR-RR)
Antenna/amplifier output

The unit uses a car tuner module, RDS-and sound processor. All this is controlled by I²C and through the PIC by USB.

I had some trouble with the prototype PCB (holes with incorrect size etc) so I adapted the PCB layout and decided to have 2 prototype PCB's made by a company nearby (had no time myself due to holiday). They're ready on friday (02/04) and will be assembled in the weekend. When they are working one will be send over to Seth for lab testing and one I keep here for testing.
If they fulfill the expectations I will most probably convert the layout to one with normal components for those who are not that big of a fan of SMT soldering (it's quite fun if I say it myself ).

Rogier

Just wanted to have some comments on design but cannot read schematics due to the small size of it. Also interesting in something similar( but simpler ) with fully digital sound.

@jbors: See the FAQ. Digital audio is within reach of the current solution -- You'd have to roll your own firmware to do the A/D sampling using either the on board converters on the 18F or with extra hardware. So too your firmware and OS USB drivers will need to deal with the audio stream.