[En-Nut-Discussion] Dallas 1-wire

[Arius - Rick Collins]

At 03:36 AM 3/29/2004, you wrote:
>Hi Thomas,
>
>It has never been included. Did you find Mike's email with
>his code? Actually you do not need a device driver. You can
>use any existing code with Nut/OS. You only need to avoid
>non-blocking loops.
>
>The advantage of device drivers is in the first place, that
>they may be used with stdio calls. In most cases this
>doesn't make much sense with 1- and 2-wire interfaces.

Actually, you can use the 1-wire interface with a UART.  You use a baud 
rate of only 115 kbps and send two different characters to represent a zero 
or a one.  Obviously the two characters have continuous bits low or high to 
generate the low pulse width required.  A reset is generated by a break 
condition.  Likewise bits received by sending a zero character and reading 
back either a zero or a one character.  The exact timing of the 0 to 1 
transition may vary depending on the loading on the bus, so a range of 
characters can be received for the zero or one response.  All of this can 
be done via stdio if I am not mistaken.




Rick Collins

rick.collins at arius.com

Arius - A Signal Processing Solutions Company
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