From: rketcham <Ric...@gm...> - 2009-06-23 22:32:35
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Hi Lewis, I forgot to mention that I actually don't have the modem attached anymore. I had monitored the voltage supply to the device (before and after the DCDC converter) and I didn't see any large voltage drop. When I wrote that last message I was just running the scripts that would interact with the modem without the modem present. The USB hub is still attached to the Gumstix and it has 3 cp2102s attached downstream. The pppd script isn't the one that's crashing - just the init script. The init script is the one I used to turn on, turn off, and restart the modem. I've since simplified the init script to simply echo and sleep. There aren't any if statements or anything done with gpio (checking via proc or manipulation). I've also turned off a number of my other init scripts. The one init script that, on the surface, seemed to make a difference was the one that started the conservative cpu governor. As it stands now, it looks like the combination of the USB hub being connected to the verdex, (see my other question on the usb hub: http://www.nabble.com/Connecting-a-USB-hub-to-Verdex-60-pin-connector-td24175235.html), the conservative governor, and some sort of loop seem to cause the reset. Although, I have seen it lockup and reset without the infinite loop but that's a little less deterministic. Rich Lewis Girod wrote: > > i still suspect power supply problems, esp since it happens when you are > turning the modem on and off. > > 1. try disconnecting the modem from the system (so it draws no power) and > then see if your pppd script still crashes (obviously it won't work but it > shouldn't crash) > > 2. hook up a scope to the power that is supplied to the gumstix to see if > you see any drop in voltage when the crash occurs > > 3. it sounds like your main power supply is sufficient but if you have a > dc/dc converter supplying the modem and gumstix, make sure that is able to > produce the required current > -- View this message in context: http://www.nabble.com/Gumstix-Freezes%2C-need-advice...-tp23952168p24175672.html Sent from the Gumstix mailing list archive at Nabble.com. |