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

Sun Jul 15 17:25:18 CEST 2012

Op zondag 15 juli 2012 16:21:06 schreef Juergen Harms:
+> 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
+
+or you could make a pci-board (or usb device with it's internal clock and 
+send/recv queue, so it's all nicely timed...
+