Re: ahb,split transfers
Hi
The ahb slave can definitely respond with a split to a locked transfer. The protocol allows for it. you can see AMBA FAQ which clearly states the following:
7. When will the arbiter grant another master after a locked transfer?
The arbiter will always grant the master an extra transfer at the end of a
locked sequence, so the master is guaranteed to perform one transfer with
the HMASTLOCK signal low at the end of the locked sequence. This coincides
with the data phase of the last transfer in the locked sequence.
During this time the arbiter can change the HGRANT signals to a new bus
master, but if the data phase of the last locked transfer receives either a
SPLIT or RETRY response then the arbiter will drive the HGRANT signals to
ensure that either the master performing the locked sequence remains
granted on the bus for a RETRY response, or the Dummy master is granted the
bus for the SPLIT response.
However giving a split or retry for a locked transfer is not recommended and will not serve the purpose for which split and retry were incorporated into the AHB Protocol.
Thanks
Prasad.