Quote:
Originally Posted by AJ Starr
I may have missed this in your descriptions, but could your computer not have enough buffer/switching memory set aside. I know in windows you can say for the system to choose or you can set it up for a specific amount.
From your description, to me, it sounds like a buffering problem.
AJ
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I really do not think that it is a buffering problem, since the problem is pretty much the same in Linux or Windows, and there is no problem at all with any other USB device. The SanDisk Cruzer memory stick got very respectable speeds for a NAND FLASH device.
I *think* the problem is in the drive strength for the USB data pair lines, causing the rise/fall times of the USB2.0 waveform being right on the edge of reliability, and causing data errors. Another one of the things that make me think that is that the PocketPRO works even worse with other USB2.0 cables than the one supplied with the PocketPRO. I have tried other USB2.0 cables, with and without the ferrite filter block, and all of them produce even worse results, up to and including the computer not even recognizing what kind of device had attached to the USB port. All of that smells like physical data integrity problems on the USB2.0 interface. Since USB1.1 uses a 10x slower main clock speed, the signal rise/fall times problems go away when USB1.1 speeds are used.