FOX Board G20 technical documentation Buy

FOX Board G20 1-wire wirings

Following is an example on how to wire a DS18B20 thermal sensor to the FOX Board G20. The resistor used to pull-up the 1-wire bus is a 4,7 KOhm.

It is possible to link more than one sensor. I tried up to five. The driver will automatically acknowledge the sensors wired.

 Note:   This example will not work using the default microSD bought from Acme after October 25, 2011 or using the R18 version available on the .
Please use the following uImage where the 1-wire bus has been moved back to J7.5 pin (PB16) as it was when I wrote this article.

Changing the 1-wire bus GPIO line

It is possible to use any GPIO line of the FOX Board because the 1-wire is not implemented in hardware but is provided by the software bit banging Linux driver called w1-gpio.c.

To select which GPIO line to use for 1-wire bus service you have to configure it by changing the board initialization code inside the Linux Kernel. The source code is board-foxg20.c and the line to change is # 215.

To get the Linux sources and compile your own Kernel image follow this article: Compiling Linux Kernel 2.6.38 for FOX Board G20 and Netus G20.

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