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USB 2.0 flash drive on USB 1.1 port

Will a USB 2.0 flash drive work on a USB 1.1 port? Also, the description of the drive says "bulk-only transport of USB mass storage class support PIO mode 4". What does that mean?

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kannabis

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Al Jee

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tirving

ASKER

Kannabis: thanks for your answer. Brand is unknown. I want to purchase it from comready.com who doesn't list the manufacturer. Is this mode significantly deficient compared to DMA? What does bulk only mean?

Al Jee

I'm not certain about the "bulk only" thing. Maybe that's a reference to burst rates. see next.

As kannabus said: the fastest PIO mode (4) has a max. transfer rate (burst) of 16.7 MB/s.

Sustained transfer rates are ALWAYS slower.

The slowest Ultra DMA [UDMA] mode 0 has the same burst rate as PIO 4 & the current mode has a burst of 133MB/s
There is a secondary advantage to DMA/UDMA.
They bypass the CPU entirely [ hence the term "direct memory access"].
This frees up the CPU and, consequently, most of the rest of the system. Doesn't bog the computer down nearly as much.

I would look around a bit.

BTW kannabus deserves the points here. ;-)

Sg

Luc Franken

No comment has been added lately, so it's time to clean up this TA.
I will leave a recommendation in the Cleanup topic area that this question is:

Split between kannabis and StoneG

Please leave any comments here within the next seven days.

PLEASE DO NOT ACCEPT THIS COMMENT AS AN ANSWER!

LucF
EE Cleanup Volunteer

Al Jee

K by me if ok w/kannabis.

Al Jee

thanx