C.2.2. APB read transfer with wait states

Figure C.4 shows how the PREADY signal can extend the transfer. The transfer is extended if PREADY is driven LOW during an Access cycle. The protocol ensures that the following remain unchanged for the additional cycles:

Figure C.4 shows that two cycles are added using the PREADY signal. However, any number of additional cycles, from zero upwards can be added.

Figure C.4. APB read transfer with wait states

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