– General Concepts
The General USB Process
How Data is Transferred in USB
Frames are made up of transfers, which are made up of transactions, which are made up of packets. The USB host schedules these 1mS frames when communicating with the low and full speed devices.
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| Frame |
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| TM |
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| Transfer |
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| Transfer |
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| Transaction |
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| Transaction |
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| Transaction |
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| Transaction |
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Software
Packet 1
Packet 2
Packet 3
Packet 1
Packet 2
Packet 3
Packet 1
Packet 2
Packet 3
Packet 1
Packet 2
Packet 3
