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AHB master related

Started by san December 22, 2004
question asked to arm on 22/12/2004
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my questions are:
1) when the master on AHB bus is getting ready signal low from slave
then is there any way the master start a new transaction on the bus.
Also if slave give the error response after some predefined number of
cycle to release the bus then is it a correct approach or is there any
better approach to release the master and bus to do other operation.
2) when the slave give retry response to master then is it possible for

the bus master to start a new transaction on the bus for same or
different slave. Is it that the particular master is blocked on getting
retry response

"san" <san_nasa@rediffmail.com> wrote in message 
news:1103713502.003743.71970@z14g2000cwz.googlegroups.com...
> question asked to arm on 22/12/2004 > ----------------------------------- > my questions are: > 1) when the master on AHB bus is getting ready signal low from slave > then is there any way the master start a new transaction on the bus. > Also if slave give the error response after some predefined number of > cycle to release the bus then is it a correct approach or is there any > better approach to release the master and bus to do other operation. > 2) when the slave give retry response to master then is it possible for > > the bus master to start a new transaction on the bus for same or > different slave. Is it that the particular master is blocked on getting > retry response >
Have you looked at the amba spec supplied on the ARM website. Proper protocol is described in that document. I believe that once a master starts an access ... it can't do anything else untl that transaction is completed. Split transacttions are available but they are intended to free up the bus for other masters to use a bus while the master that is split waits for the slave to be ready. A retry is just that ... the master retries its cycle to that slave. Again it is best to read the spec. ... I believe these types of transactions are adequatly described. Mike