TinyCircuits Forum

TinyCircuits Products => TinyDuino Processors & TinyShields => Topic started by: jbennett on October 13, 2015, 10:57:58 PM

Title: FONA 808 and TinyDuino with Proto Board
Post by: jbennett on October 13, 2015, 10:57:58 PM

I'm looking to use the FONA 808 (https://learn.adafruit.com/adafruit-fona-808-cellular-plus-gps-breakout?view=all) with the TinyDuino with Li battery support (https://www.tiny-circuits.com/tinyduino-processor-board.html), TinyShield Accelerometer (https://www.tiny-circuits.com/tiny-shield-accelerometer.html), the TinyShield Protoboard (https://www.tiny-circuits.com/tiny-shield-proto-board-all-163.html), and potentially Mifare MFRC522 RFID Reader/Writer (http://playground.arduino.cc/Learning/MFRC522).

I'm relatively new to this stuff but I'm wanting to try and learn.  I'm a bit confused by this (http://forum.tiny-circuits.com/index.php?topic=228.0) thread. The MFRC522 appears to require 3.3v.  I'm seeing where the TinyDuino no longer provides a 3.3v rail.  Would I basically need to wire the MFRC522 to the Protoboard and use a step-down to bring it from 5v to the necessary 3.3v?

From there, I should be good to go, correct?

Title: Re: FONA 808 and TinyDuino with Proto Board
Post by: Ben Rose on October 15, 2015, 03:10:07 PM

You'll need a regulator plus level shifting for any output pins to the chip- if it's low speed SPI, that can be a resistor divider. Another option is finding a board with built in regulation and level shifting, like FONA and our accelerometer board have, which makes things a lot easier.

Sounds like an interesting project!