[Mageia-discuss] One-Wire Home Temperature Network with Linux

Sun Jul 15 16:21:06 CEST 2012

On 07/15/2012 03:13 PM, Doug Lytle wrote:
+> I've just started to play with a 1 wire temperature sensor, under Mageia
+> 1. I've been following a couple of blog on how to get things setup (1 & 2).
+>
+> I've installed the digitemp software (2) via urpmi and can actually see
+> the USB dongle (DS9490R) and my temp sensor (DS18B20).
+>
+> The problem being that when running the command digitemp_DS2490 -a -i
+> -q, it is supposed to write out it's configure file (.digitemprc) to the
+> profile directory, which for me running the command as root, should be
+> /root/.digitemprc, but it doesn't.
+>
+> Has anybody played around with temperature sensors under Mageia? If so,
+> were you able to get it to write out the file?
+>
+> Doug
+>
+> (1)
+> http://bitsup.blogspot.com/2008/11/one-wire-home-temperature-network-with.html
+>
+> (2) http://www.nslu2-linux.org/wiki/HowTo/AddUSBOneWireAdapter
+> (3) http://digitemp.com
+>
+
+I have DS18B20 sensors running, but not on Mageia - my sensors are 
+connected to an AVR microprocessors (which is controlled by a C 
+programme, downloaded from my Mageia PC).
+
+I have doubts whether it is possible to reliably operate 1-wire devices 
+directly connected to a PC that is simultaneously used to do "ordinary 
+stuff": the 1-wire protocol has quite strict bit-timing requirements 
+(the pin on the I/O port on your PC which drives the 1-wire bus must 
+create pulses with well-defined lengths and intervals), not evident to 
+implement on a time-shared PC - could also have negative impact on non 
+real-time applications that run on the PC. You might need to more or 
+less dedicate your PC to run your 1-wire application.
+
+In case you cannot make it work directly on Mageia, the microprocessor 
+approach is certainly a valid (even better?) alternative since the 
+microprocessor can print the result to a serial port and hence to a PC.
+
+In case this approach is of interest to you, we should discuss this by 
+PM (no problem to let you have my hard- and software)
+
+Juergen
+