HD6417615 Hitachi Semiconductor, HD6417615 Datasheet - Page 332

• Manufacturer Part Number: HD6417615
• Description: Hardware Manual
• Manufacturer: Hitachi Semiconductor

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. In the SH7615, the REFOUT pin is provided to send a signal
requesting the bus right during the wait for refreshing to be executed. REFOUT is asserted until
the bus is acquired. 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.
CKIO
CKE
A10
CS2 or CS3
RAS
CAS
RD/WR
DQMxx
Tp
Trr
Figure 7.31 Self-Refresh Timing
Trc
Trc
Trc
Trc
Trc
Tre
315