AXI Outstanding or Active transaction

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Active transaction or Outstanding transaction for AXI 

Definition of outstanding transaction on Read Channel :


Read address is placed and waiting for the read data.
Number of such AR transaction accepted between read address and last read data for the particular read address is simply the number of outstanding transaction on read channel

Definition of outstanding transaction on Write Channel :
For write transactions, the data can come after the address, but leading write data is also
allowed. The start of a write transaction can therefore be either of the following:
• The transfer of the write address
• The transfer of leading write information
Therefore, an active write transaction is a transaction for which the write address or leading write
data has been transferred, but the write response has not yet been transferred.

Simply we can say the number of transaction accepted on AW channel between first AW and the Bresp on the write channel will give outstanding transaction on write channel


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