Hi
In my workplace I was asked a question and I'm quite unable to answer.
A worker ask why 1 USB thumb drive takes longer than other to get connected (about 5 seconds).
We have a processor board with network connectivity that we instal CAN and serial port drivers from an USB thumb drive. Recently 1 USB drive dropped dead, so we switched it to another (same software).
It used to take about 2-3 seconds for the processor board to indicate the USB was connected but now it takes nearly 10s.
What could make such a difference?
I've also noticed similar differences in windows, some USB drives take a lot longer to get recognized (even if driver is already installed). Is the software to initiate connection so different?

Thanks

 

When a USB device is introduced there is a process called enumeration that takes place. It is a non-deterministic series of questions and answers that is used to determine the capabilities and features of the device. Would you really expect ALL manufacturers to implement their devices in the identical way? If so, you have a naive view of commerce in the global environment.

 

I get that there are differences how USB sticks communicate. Is it determined in its driver?
But what makes for so big differences, some take a couple of seconds, others nearly 30s?

 

hi, question is already answered in post #2

putting it into simple terms, you get what you pay for.

example, one of my clients bought from china some client giveaway 8gb memory sticks for christmas last year. they looked ok until you plugged them into a usb port. same problem as your varying detect issue, and painfully slow to put data (if at all) on them. all 200 went straight in the bin.

you have better quality control with respectable name brands,