I think most of us have seen the occasional failures from these EMC effects, but without your setup and observations it would be hard to hunt down. Again, thank you.
Paul -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of Jan Kandziora Sent: Monday, June 27, 2005 5:35 AM To: owfs-developers@lists.sourceforge.net Subject: Re: [Owfs-developers] More on "Hanging" Problems Am Montag, 27. Juni 2005 05:26 schrieb Gregg C Levine: > Hello from Gregg C Levine > Paul, explain this phrase in better detail please: > "In any case, it's great that Jan has a setup where he can > consistently trigger the errors." In an embedded an environment it is > sometimes considered desirable to stress test the file system by > triggering power cycles. There's an article on that, and the methods > used somewhere on the Linux-MTD site. > What I do isn't stress-testing. That would mean to get parameters when some component will probably fail and has to be replaced. That's not what I'm after, at least at the moment. I just ran into that failure - it makes 1-wire completely unusable for my application. > Now I can see for myself how a rigged system would be desirable for > stress testing the file system that we've created. But a detailed > explanation would be good thing. > > Jan, what are you running? Which distribution? What is the hardware > configuration? I walked into this meeting late, and left my agenda and > most of my notes in a different location. > I'm designing a semiautomatic vending machine with a lot of attached devices (flow-rate sensors and solenoid driven valves), most of them in a ten-meter range around the machine, but some of them about 100m far away. The computer which will be built into this will be a MIPS based embedded board, which isn't completed yet. The computer I use to test is a Gene6310 "embedded" (more like barebone) PC board. Its i386-family based. This computer is working and would be used as a backup solution, if the MIPS board is not completed in time. I have a testbench, where I can arrange the devices like they were already put into that vending machine. I hooked up the 1-wire to USB via a off-the-shelf DS9490 adapter to the barebone. There is a mains transformer 230/24V~ 150W (completely passive, not a switching one), which is the power supply for the sensors and solenoids. The actual transformer for the machine will be a 400W type, which makes things even worse. This mains transformer generates some kind of EMC when switching it "ON" or "OFF" with an ordinary 230V switch. This is understandable if the switching happens outside of the zero-cross of voltage (ON-switching) or current (OFF- switching). The EMC pulse causes either the USB or the 1-wire (or both) to disconnect - which leads owfs into an unusable state. I'm pretty sure I can minimize this EMC by putting a zero-cross and snubbing circuit into my transformer - but I'm very unsure other appliances in the pub or gas station where the vending machines will be mounted are so kind. That's why I think we have to be able to recover from this error automatically. Kind regards Jan -- There's light at the other end of the the Windows. ------------------------------------------------------- SF.Net email is sponsored by: Discover Easy Linux Migration Strategies from IBM. Find simple to follow Roadmaps, straightforward articles, informative Webcasts and more! Get everything you need to get up to speed, fast. http://ads.osdn.com/?ad_id=7477&alloc_id=16492&op=click _______________________________________________ Owfs-developers mailing list Owfs-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/owfs-developers ------------------------------------------------------- SF.Net email is sponsored by: Discover Easy Linux Migration Strategies from IBM. Find simple to follow Roadmaps, straightforward articles, informative Webcasts and more! Get everything you need to get up to speed, fast. http://ads.osdn.com/?ad_idt77&alloc_id492&op=click _______________________________________________ Owfs-developers mailing list Owfs-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/owfs-developers
