Hey guys,
Part of my final year project requires interfacing an ibutton to a embedded computer to serve as a user authentication feature.
My supervisor has handed me two things, namely;
a) ibutton ,model: DS1990A which is an ID only ibutton
b) ibutton reader, model: DS9092 which is has two wires coming out(1 for power and one for data(ibuttons use the 1-wire interface))
My question is, can I interface the ibutton reader to a PC using the USB interface? There are USB adapters for sale which is a basically a reader with a built in USB connector. However, I would like to construct one on my own.
Since the ibutton model only allows reading, can I just connect the data wire of the reader to the data pin of the USB jack and forget about the write pin on the USB connector. If I connect the power wire on the ibutton reader to the USB Vcc, where do I connect to USB ground to?
Has anyone done this? Thanks in advance folks