Refresh - Hitachi SH7095 Hardware User Manual

Figure 7.41 Static Column Mode
7.7.5

Refresh

The BSC has a function for controlling pseudo SRAM refreshing. By setting the MCR's RMODE
bit to 0 and RFSH bit to 1, a scattered refresh using the auto-refresh cycle can be performed.
Refreshes are performed at the interval determined by the input clock selected in CKS2–CKS0 of
the RTCSR and the value set in the RTCOR. Set the values of RTCOR and CKS2–CKS0 so they
satisfy the refresh interval specifications of the pseudo SRAM being used. First, set the RTCOR,
RTCNT and the RMODE and RFSH bits of the MCR, then set the CKS2–CKS0 bits. When a
clock is selected with the CKS2–CKS0 bits, RTCNT starts counting up from the value at that
time. The RTCNT value is constantly compared to the RTCOR value and a request for a refresh is
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