Bit 7—Self-Refresh Mode (SRFMD): Specifies DRAM or pseudo-static RAM self-refresh
during software standby mode. When PSRAME = 1 and DRAME = 0, after the SRFMD bit is set
to 1, pseudo-static RAM can be self-refreshed when the H8/3048 Series enters software standby
mode. When PSRAME = 0 and DRAME = 1, after the SRFMD bit is set to 1, DRAM can be self-
refreshed when the H8/3048 Series enters software standby mode. In either case, the normal
access state resumes on exit from software standby mode.
Bit 7
SRFMD Description
0
DRAM or PSRAM self-refresh is disabled in software standby mode
(Initial value)
1
DRAM or PSRAM self-refresh is enabled in software standby mode
Bit 6—PSRAM Enable (PSRAME) and Bit 5—DRAM Enable (DRAME): These bits enable
or disable connection of pseudo-static RAM and DRAM to area 3 of the external address space.
When DRAM or pseudo-static RAM is connected, the bus cycle and refresh cycle of area 3
consist of three states, regardless of the setting in the access state control register (ASTCR). If
AST3 = 0 in ASTCR, wait states cannot be inserted.
When the PSRAME or DRAME bit is set to 1, bits 0, 2, 3, and 4 in RFSHCR and registers
RTMCSR, RTCNT, and RTCOR are write-disabled, except that the CMF flag in RTMCSR can be
cleared by writing 0.
Bit 6
Bit 5
PSRAME
DRAME
Description
0
0
Can be used as an interval timer
(Initial value)
(DRAM and PSRAM cannot be directly connected)
1
DRAM can be directly connected
1
0
PSRAM can be directly connected
1
Illegal setting
151
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