How do split response and retry work for the AHB protocol?

 How do split response and retry work for the AHB protocol?

Split and retry response are the different responses fed from the slave side along with ok and error response.

The difference between them is that retry will only take care of the high priority master but split will take care of the lower priority master and gives the access of the bus to them so that no master will die in starvation. 

The master will initiate the read and write operation and provide address and control information.If the slave able to provide the response within the given time frame it will do so otherwise it will free up the bus to be used by the other master.The master must rearbitrate again to gain access to the bus.

Correspondingly when the slave is ready to acknowledge it will assert the appropriate bit on Hsplitx[15:0],by continuously monitoring the Hamster signal.This Hamster signal is basically used for split response to keep track on the master who are using the bus.

For more information obviously you can refer the AHB AMBA spec of ARM.

Note that split and retry response you will only able to find in the earlier versions of AHB AMBA spec as the latest one AHB5 spec removes those and only OK and Error response prevails.

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