HD6413002 Datasheet, PDF (191/700 Pages) Renesas Technology Corp – High-performance single-chip microcontroller

• Refresh cycles are not executed while the bus is released, during software standby mode, and
when a bus cycle is greatly prolonged by insertion of wait states. When these conditions
occur, other means of refreshing are required.
• If refresh requests occur while the bus is released, the first request is held and one refresh
cycle is executed after the bus-released state ends. Figure 7-24 shows the bus cycles in this
case.
Bus-released state Refresh cycle CPU cycle Refresh cycle
ø
RFSH
Refresh
request
BACK
Figure 7-24 Refresh Cycles when Bus is Released
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