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owfs performance with DS2480-800 and DS18S20

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	owfs performance with DS2480-800 and DS18S20 by Mark Ter Morshuizen :: Rate this Message: \| View Threaded \| Show Only this Message Hi, I have an osif USB to I2C adapter ( http://www.headfuzz.co.uk/?q=USBtoI2C ) connected to a Maxim DS2480-800 8 channel 1-wire bus master. I have a single DS18S20 one each of 4 busses of the DS2480. Getting temperature readings from 4 sensors takes anything up to about 30 seconds using owread and owserver on a 700MHz embedded PC system. Is this normal? If so can anything be done to speed things up? The 1-wire network is static (devices are seldom added or removed) so perhaps some discovery can be turned off or some such? Could the bus scans be limited to the busses I'm actually using? I didn't see this sort of delay while using I2C temperature sensors so I'm assuming that the osif adapter is OK. Thanks, -- Mark Ter Morshuizen ------------------------------------------------------------------------------ Keep Your Developer Skills Current with LearnDevNow! The most comprehensive online learning library for Microsoft developers is just $99.99! Visual Studio, SharePoint, SQL - plus HTML5, CSS3, MVC3, Metro Style Apps, more. Free future releases when you subscribe now! http://p.sf.net/sfu/learndevnow-d2d _______________________________________________ Owfs-developers mailing list Owfs-developers@... https://lists.sourceforge.net/lists/listinfo/owfs-developers
	Re: owfs performance with DS2480-800 and DS18S20 by Patryk-6 :: Rate this Message: \| View Threaded \| Show Only this Message Dnia 24-01-2012 o 06:57:09 Mark Ter Morshuizen <mark@...> napisał(a): > from > 4 sensors takes anything up to about 30 seconds using owread and > owserver on a You mean DS2482-800? I think it's too long. DS2482-800 has 8 separate outputs. It has to "switch" between outputs but while one output is used for data transfer other ones have power so the sensor can use parasite power. DS18b12 first gets a command to convert temperature which should take about 1s in this time all communication is stopped to supply power to the sensor after that the temperature should be available and master asks for it. > Is this normal? If so can anything be done to speed things up? The 1-wire > network is static (devices are seldom added or removed) so perhaps some You can try to write 1 to the /simultaneous/temperature and then read temperatures. In theory it should work but I don't know if it's implemented. The other solution is to read temp with less precision /sensor/temperature9 However on my 200Mhz router with DS2480B serial converter reading one parasite powered sensor take 1.22 seconds and it's with full precision. So maybe something else is wrong with your setup. Maybe the i2c<->usb converter add so much overhead? -- p4trykx ------------------------------------------------------------------------------ Keep Your Developer Skills Current with LearnDevNow! The most comprehensive online learning library for Microsoft developers is just $99.99! Visual Studio, SharePoint, SQL - plus HTML5, CSS3, MVC3, Metro Style Apps, more. Free future releases when you subscribe now! http://p.sf.net/sfu/learndevnow-d2d _______________________________________________ Owfs-developers mailing list Owfs-developers@... https://lists.sourceforge.net/lists/listinfo/owfs-developers
	Re: owfs performance with DS2480-800 and DS18S20 by Paul Alfille-2 :: Rate this Message: \| View Threaded \| Show Only this Message >From the headfuzz website: Linux/Mac Install the libusb package from your package manager. If you want to compile from source you will need libusb-dev too. Everything else will work out of the box. Linux users can insmod the kernel module supplied in the CVS tree to access via the faster /dev/i2c-x interface. Have you tried this? Paul Alfille On Tue, Jan 24, 2012 at 5:21 AM, p4trykx <p4trykx@...> wrote: Dnia 24-01-2012 o 06:57:09 Mark Ter Morshuizen <mark@...> napisał(a): > from > 4 sensors takes anything up to about 30 seconds using owread and > owserver on a You mean DS2482-800? I think it's too long. DS2482-800 has 8 separate outputs. It has to "switch" between outputs but while one output is used for data transfer other ones have power so the sensor can use parasite power. DS18b12 first gets a command to convert temperature which should take about 1s in this time all communication is stopped to supply power to the sensor after that the temperature should be available and master asks for it. > Is this normal? If so can anything be done to speed things up? The 1-wire > network is static (devices are seldom added or removed) so perhaps some You can try to write 1 to the /simultaneous/temperature and then read temperatures. In theory it should work but I don't know if it's implemented. The other solution is to read temp with less precision /sensor/temperature9 However on my 200Mhz router with DS2480B serial converter reading one parasite powered sensor take 1.22 seconds and it's with full precision. So maybe something else is wrong with your setup. Maybe the i2c<->usb converter add so much overhead? -- p4trykx ------------------------------------------------------------------------------ Keep Your Developer Skills Current with LearnDevNow! The most comprehensive online learning library for Microsoft developers is just $99.99! Visual Studio, SharePoint, SQL - plus HTML5, CSS3, MVC3, Metro Style Apps, more. Free future releases when you subscribe now! http://p.sf.net/sfu/learndevnow-d2d _______________________________________________ Owfs-developers mailing list Owfs-developers@... https://lists.sourceforge.net/lists/listinfo/owfs-developers ------------------------------------------------------------------------------ Keep Your Developer Skills Current with LearnDevNow! The most comprehensive online learning library for Microsoft developers is just $99.99! Visual Studio, SharePoint, SQL - plus HTML5, CSS3, MVC3, Metro Style Apps, more. Free future releases when you subscribe now! http://p.sf.net/sfu/learndevnow-d2d _______________________________________________ Owfs-developers mailing list Owfs-developers@... https://lists.sourceforge.net/lists/listinfo/owfs-developers
	Re: owfs performance with DS2480-800 and DS18S20 by Mark Ter Morshuizen :: Rate this Message: \| View Threaded \| Show Only this Message Hi Paul, Thanks for the reply. On Tuesday 24 January 2012 17:53:59 Paul Alfille wrote: > >From the headfuzz website: > Linux/Mac > Install the libusb package from your package manager. If you want to > compile from source you will need libusb-dev too. Everything else will work > out of the box. Linux users can insmod the kernel module supplied in the > CVS tree to access via the faster /dev/i2c-x interface. > > Have you tried this? Yes, I'm using the kernel module. I had it working for about 3 months with LM75 I2C sensors. It worked quite well but I was limited to a couple of sensors because I2C doesn't like long distances. Cheers, -- Mark Ter Morshuizen mark@... www.itbox.co.za 082 542 6484 2U Rackmount Casings: http://www.rackmount.co.za ------------------------------------------------------------------------------ Keep Your Developer Skills Current with LearnDevNow! The most comprehensive online learning library for Microsoft developers is just $99.99! Visual Studio, SharePoint, SQL - plus HTML5, CSS3, MVC3, Metro Style Apps, more. Free future releases when you subscribe now! http://p.sf.net/sfu/learndevnow-d2d _______________________________________________ Owfs-developers mailing list Owfs-developers@... https://lists.sourceforge.net/lists/listinfo/owfs-developers