Applies to:AMBA AHB

The following examples show some of the sequences of HTRANS that can occur on the bus:

A normal burst of four transfers followed by an IDLE.
N - S - S - S - I

A normal burst of four transfers which includes BUSY transfers.
N - S - B - S - B - S - I

A burst of four transfers followed by another burst.
N - S - S - S - N - S - S - S - I

A single transfer followed by a burst of four transfers.
N - N - S - S - S - I

A single transfer followed by an IDLE
N - I

An undefined length burst which concludes with a BUSY transfer.
N - B - S - B - S - B - I

An undefined length burst which concludes with a BUSY transfer and is followed immediately by another burst.
N - B - S - B - S - B - N - S

See also:

• AMBA 2.0 Specification
• Can a BUSY transfer occur at the end of a burst?
• Can a master change the address/control signals during a waited transfer?
• Do all slaves have to support the BUSY transfer type?
• Can HTRANS change whilst HREADY is low?
• What value should be used for HTRANS when an AHB master gets a RETRY response from a slave in the middle of burst?

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