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12-31-04, 02:59 PM

I know we have discused this before BUT I have some new information. If all you want is the warning skip the next paragraph.

I have found that the +5v from USB and the +5.4v from the wall plug DO come into the axim x50 from differant pins. When looking at the cable (not the axim) with the pins down the +5v is I think the 3rd over from the left on the second set of pins and the +5.4v is the rightmost pin or close to it. (hard to give exact pins without taking it apart). I figured this out using a Dell USB sync cable and a multimeter. As long as there is nothing between the two ends of the cable you just check the resistance between the pins on each end of the cable if the resistance is low such as 3 ohms then they are continuous through the cable.

What this means to you. Most of the direct sync cables and sync/charge cables made by third partys have the +5v from the USB port running to your +5.4v on the axim. While this will not damage the axim (it may damage the computer but should not). It is not correct and at the least these companys should be putting a switch on the cable so you can select where the power goes if it goes to the +5v pin or the +5.4v pin.

When the power runs to the +5v pin the system knows not to charge unless its turned off then to only charge at 500mA which is the max a USB port is able to put out under USB specs. When attached directly to a computer normally what will happen is you try to draw too much current and the port turns off. Some cheap hubs don't have this limit and will supply the extra current and normally is not a problem either.

This is why some people have problems with these cables and others do not. Some computers can handle it or don't have current limiters in place. Others are able to stay under 500mA by not having a dead battry or other high current items running.

About the switch I brought up earlier. If a switch is on the cable you can have the power go to the +5v pin to charge a dead battery then when its charged you can flip the switch to have the power go to the +5.4v pin so you can maintain the battery while using the axim or do a light charge while connected to the computer. This way it can charge and sync at the same time when possible and when its not possible just charge.

EDIT: So in the end if it syncs and charges AT THE SAME TIME through only USB then I would not buy it unless it had a switch you know the device that will be supplying the power can handle large loads. (which most of the wall chargers etc can not do)

12-31-04, 02:59 PM	#1 (permalink)
Kenban Guest Posts: n/a	USB sync/charge cable warning I know we have discused this before BUT I have some new information. If all you want is the warning skip the next paragraph. I have found that the +5v from USB and the +5.4v from the wall plug DO come into the axim x50 from differant pins. When looking at the cable (not the axim) with the pins down the +5v is I think the 3rd over from the left on the second set of pins and the +5.4v is the rightmost pin or close to it. (hard to give exact pins without taking it apart). I figured this out using a Dell USB sync cable and a multimeter. As long as there is nothing between the two ends of the cable you just check the resistance between the pins on each end of the cable if the resistance is low such as 3 ohms then they are continuous through the cable. What this means to you. Most of the direct sync cables and sync/charge cables made by third partys have the +5v from the USB port running to your +5.4v on the axim. While this will not damage the axim (it may damage the computer but should not). It is not correct and at the least these companys should be putting a switch on the cable so you can select where the power goes if it goes to the +5v pin or the +5.4v pin. When the power runs to the +5v pin the system knows not to charge unless its turned off then to only charge at 500mA which is the max a USB port is able to put out under USB specs. When attached directly to a computer normally what will happen is you try to draw too much current and the port turns off. Some cheap hubs don't have this limit and will supply the extra current and normally is not a problem either. This is why some people have problems with these cables and others do not. Some computers can handle it or don't have current limiters in place. Others are able to stay under 500mA by not having a dead battry or other high current items running. About the switch I brought up earlier. If a switch is on the cable you can have the power go to the +5v pin to charge a dead battery then when its charged you can flip the switch to have the power go to the +5.4v pin so you can maintain the battery while using the axim or do a light charge while connected to the computer. This way it can charge and sync at the same time when possible and when its not possible just charge. EDIT: So in the end if it syncs and charges AT THE SAME TIME through only USB then I would not buy it unless it had a switch you know the device that will be supplying the power can handle large loads. (which most of the wall chargers etc can not do) Last edited by Kenban; 12-31-04 at 03:05 PM.