Datasheet

Section 6 Bus Controller
Rev.6.00 Sep. 27, 2007 Page 163 of 1268
REJ09B0220-0600
Bit 4—Compare Match Flag (CMF): Status flag that indicates a match between the values of
RTCNT and RTCOR.
When refresh control is performed (RFSHE = 1), 1 should be written to the CMF bit when writing
to DRAMCR.
Bit 4
CMF Description
0 [Clearing condition]
Cleared by reading the CMF flag when CMF = 1, then writing 0 to the CMF flag
(Initial value)
1 [Setting condition]
Set when RTCNT = RTCOR
Bit 3—Compare Match Interrupt Enable (CMIE): Enables or disables interrupt requests (CMI)
by the CMF flag when the CMF flag in DRAMCR is set to 1.
When refresh control is performed (RFSHE = 1), the CMIE bit is always cleared to 0.
Bit 3
CMIE Description
0 Interrupt request (CMI) by CMF flag disabled (Initial value)
1 Interrupt request (CMI) by CMF flag enabled
Bits 2 to 0—Refresh Counter Clock Select (CKS2 to CKS0): These bits select the clock to be
input to RTCNT from among 7 internal clocks obtained by dividing the system clock (φ). When
the input clock is selected with bits CKS2 to CKS0, RTCNT begins counting up.
Bit 2
CKS2
Bit 1
CKS1
Bit 0
CKS0 Description
0 0 0 Count operation disabled (Initial value)
1 Count uses φ/2
1 0 Count uses φ/8
1 Count uses φ/32
1 0 0 Count uses φ/128
1 Count uses φ/512
1 0 Count uses φ/2048
1 Count uses φ/4096