Add external devices to your iPhone using just the audio jack

Eddie on the newtech-1 mailing list posted this article

"CNET: "Twitter co-founder's 'Square' comes into focus"Looks like a neat iPhone attachment that turns your phone into a portable credit card reader."

To which my reply was;
Hmmm “that fits in to the headphone jack of an iPhone” Oh really?
I wonder how they are achieving that?


Calvin was able to provide this link; http://bit.ly/iPhone_Serial_Hack

So technically I could build a keyboard for the iphone using it’s ‘audio jack’ or any other type of external device as long as it didn’t need anything more than a 1200 baud data rate.

Very interesting, wonder if anyone else is planning things along this line.


Cheers,
Dean