There seems to be yet another SirfIII based boards out there called the EM408, the nice thing I liked about this board is a 3.3V supply and a SMA for external antennas.
However I can’t figure out if its possible to buy this thing. SFE when are you’ll planning to stock these?
I had a few other questions about integrating that into a board :
- Ryan (ohararp): you seem to have a couple of charge pumps on your board to supply a constant voltage to the PIC micro and the GPS, just curious if you have any issues with the noise? I'm guessing the GPS board has enough decoupling to filter that but the MCU?
I can’t figure out why the 3.3V input on the EM408 would result in a peak 2.85V signal? (should I still consider a level translation circuit to get it talking to my 3.3V MCU?)
I’m playing with the idea of using a HCS08 (GT/GB) to buffer and store data to a SD card (I use that micro at work and have the pods to program it) But I can’t seem to find any sources to get that micro to read/write to a FAT16 FS.
- Anyone have any code for that MCU?
Any suggestions for other micros which have
- "VERY" cheap programming pods,
free compiler tool chain,
easily available eagle footprints (small QFN preferred))
easily available SD(FAT16) read/write code.
can any one think of any reason why not to place a micro/sd directly below the GPS module (on a double sided carrier board?) I want to make a really small board.
50 mV of ripple is all that I am getting out of these cahrge pumps and I haven’t had any problems.
Finding a “complete” FAT16 file system will be tough. Definitely recommend www.picbasic.org for this. I think that SWRIGHTS work on this has been awesome and I have found it to no only be complete but very robust.
I have not tried interfacing with a 3.3V uPic but I imagine you should not need any logic shifting.
Opps, i ordered them from work, what happened is they noticed my account and since we order OEM of another model then gave me a discount for these singles.