HD6413003TF10 Datasheet, PDF (191/717 Pages) Renesas Technology Corp – Old Company Name in Catalogs and Other Documents

7.4 Interrupt Source
Compare match interrupts (CMI) can be generated when the refresh controller is used as an
interval timer. Compare match interrupt requests are masked/unmasked with the CMIE bit of
RTMCSR.
7.5 Usage Notes
When using the DRAM or pseudo-static RAM refresh function, note the following points:
• 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 7-23 shows the bus cycles in this
case.
Bus-released state Refresh cycle CPU cycle Refresh cycle
ø
RFSH
Refresh
request
BACK
Figure 7-23 Refresh Cycles when Bus is Released
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