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...
