Interfacing phone and board

kinghigh

We are using the INA 219 DC Current Sensor to be able to measure the current, voltage, and resistance to mimic a multimeter. We are then sending the signal through the auxiliary jack of an iPhone. Then an app will read and display the data like the LCD screen of a multimeter. Right now we are working on programming the INA 219 DC Current Sensor on BASIC stamp/PBASIC. What code would we use to be able to send this data through an output? And then receive data from the phone?

Mike Green

Can't give you an answer without more information about the interface between the Stamp and the iPhone. If you're talking about a serial port on the iPhone and you've already found a source for the hardware needed on the iPhone side, then you could probably just use SERIN and SEROUT. If you're trying to use the audio input / output of the iPhone, that depends again on the interface. A Stamp can generate DTMF signals with the FREQOUT statement which can provide 4 bits at a time to the iPhone with some filtering (see the Stamp Manual for details). There's no corresponding receive decoding and you'd have to use a DTMF decoder. Here's one example. There are others you can find on the web searching for "dtmf decoder stamp".