Asyncronous 1-wire interface?

Leo Havmøller skrev:

I know of a single wire interface, which is bidirectional and multiplexes data with VCC and GND on a single wire.

Two units, one have a battery and the other one does not have any power source, but is powered, when in contact with the first unit through the single wire.

Cant reveal any details, but it is a known fact that it is easier to solve a problem, once one knows it is solvable ;-)

Leo Havmøller skrev:

I know of a single wire interface, which is bidirectional and multiplexes data with VCC and GND on a single wire.

Two units, one have a battery and the other one does not have any power source, but is powered, when in contact with the first unit through the single wire.

Cant reveal any details, but it is a known fact that it is easier to solve a problem, once one knows it is solvable ;-)

Sounds like a novel application of an RFID chip.

he

ock

You didn't give the IEEE spec you found.

BTW, your original problem has been solved many times before. You need to have some sort of timing reference, but then when the clock is shut down, I would expect the chip is not active either... so I don't think that is a problem. Even if the timing reference varies, the data can be recovered. Think of a signal source where the clocking rate changes during the message. It is something I am sure you see in action nearly every day.

Rick

I would like to see that interface. I guess it is capacitively coupled and uses a charge pump to maintain power level? Or maybe you aren't describing it correctly when you say Vcc and GND are muxed on the same wire??? The 1-wire protocol I am familiar with uses a wire for everything else and a second wire for ground.

Rick

Sounds to me like a device that is overspecified and could use a 1- wire interface... "1-wire" as in the Dallas interface. Bloody hell, if the clock is turned off, how does the chip run??? When a transition is detected, start the clock and read the message!

Rick