SH7604 Datasheet, PDF (192/633 Pages) Hitachi Semiconductor – Hardware Manual

Refresh Requests and Bus Cycle Requests: When a refresh request occurs while a bus cycle is
executing, the refresh will not be executed until the bus cycle is completed. When a refresh request
occurs while the bus is released using the bus arbitration function, the refresh will not be executed
until the bus is recaptured. If RTCNT and RTCOR match and a new refresh request occurs while
waiting for the refresh to execute, the previous refresh request is erased. To make sure the refresh
executes properly, be sure that the bus cycle and bus capture do not exceed the refresh interval.
If a bus arbitration request occurs during a self-refresh, the bus is not released until the self-refresh
is cleared. During a self-refresh, the slave chips halt if there is a master-slave structure.
CKIO
CKE
A10
CS2 or
CS3
RAS
CAS
WE
DQMxx
BS
Tp Trr Trc
Trc Trc Trc Trc Tre
Figure 7.26 Self-Refresh Timing
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