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Thread ID: 86516	2008-01-19 21:15:00	Paging Electronics Experts - USB Hub Issue	somebody (208)	PC World Chat

Post ID	Timestamp	Content	User
631876	2008-01-19 21:15:00	I have been preparing the various components needed for a USB hub mod for my Asus Eee PC, however have run into a problem. I purchased a cheap, 4-port USB hub (similar to www.trademe.co.nz but USB2.0), and have tried to remove what I can from the PCB (LED, DC-IN socket). After that, the hub seemed to produce a lot of errors when plugging it into a PC about an "Unknown Device", but unfortunately I didn't investigate thoroughly. After discovering that the hub "seemed" to work with a USB flash drive plugged in despite the errors, I kept on going with cleaning up the PCB where I'd caused some damage, and trying to further strip it down. I chopped off one end of the PCB going to the 4th USB socket, in an effort to conserve space - I intend to use the two USB sockets on the far right for USB flash drive + something else, and the one on the left (with socket removed) for the webcam. See www.imagef1.net.nz The problem is that the two ports on the right work fine, but the two on the left are registering "Unknown Device" when the hub is plugged in, even though they have nothing connected (and one is missing altogether since I chopped it off). Does anyone have any ideas as to what I may have broken to cause this? I have checked several connections which I thought I may have broken, and re-soldered them just to be safe.	somebody (208)
631877	2008-01-19 21:44:00	the chip might need the load resistors across some pins. there are a couple of resistors/capacitors on the bit of board that your cut off. may pay to lookup a spec sheet of the chip and see what it needs to be happy.	robsonde (120)
631878	2008-01-19 22:32:00	the chip might need the load resistors across some pins. there are a couple of resistors/capacitors on the bit of board that your cut off. may pay to lookup a spec sheet of the chip and see what it needs to be happy. I ran a multimeter over the lower resistor (has 000 stamped on it), and it's near 0 ohms. Following the wiring, it appears to just be the +5V line, and they've used a "resistor" to go over the top of the thin data lines. The other 2 resistors are 15K ohm between Data+ to Ground, and Data- to Ground. I have a suspicion that I may have broken it before I cut off that bit, however I wasn't thinking clearly and didn't thorougly investigate.	somebody (208)
631879	2008-01-19 22:45:00	Just had a read through the datasheet (pdf1.alldatasheet.com), and there is no mention of any particular configuration to keep the chip happy. I'm going to have to cut off the 3rd port now, as after further investigation, I cannot physically fit this into my Eee in its current size.	somebody (208)
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