FOX Board G20 technical documentation
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.
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.
- Download uImage file with 1-wire on J7.5 (MD5: fdcdd314ecf6d9985d4af58dba2cfc60)
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.
