HD6417705F133V Datasheet, PDF (204/741 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperH RISC engine Family/SH7700 Series

• Wait control register for CS6B space (CS6BWCR)
• SDRAM control register (SDCR)
• Refresh timer control/status register (RTCSR)*¹
• Refresh timer counter (RTCNT)*¹
• Refresh time constant register (RTCOR)*¹
• SDRAM mode register for CS2 space (SDMR2)*²
• SDRAM mode register for CS3 space (SDMR3)*²
Notes: 1. This register only accepts 32-bit writing to prevent incorrect writing. In this case, the
upper 16 bits of the data must be H'A55A, otherwise writing cannot be performed.
When reading, the upper 16 bits are read as H'0000.
2. The contents of this register are stored in SDRAM. When this register space is
accessed, the corresponding register in SDRAM is written to. For details, refer to
section 7.8.10, Power-On Sequence.
7.4.1 Common Control Register (CMNCR)
CMNCR is a 32-bit register that controls the common items for each area. Do not access external
memory other than area 0 until the CMNCR register initialization is complete.
Bit
Bit Name
31 to 8 
Initial
Value R/W
0
R
7
DMAIW1 0
R/W
6
DMAIW0 0
R/W
Description
Reserved
These bits are always read as 0. The write value should
always be 0.
Wait states between access cycles when DMA single address
transfer is performed.
Specify the number of idle cycles to be inserted after an
access to an external device with DACK when DMA single
address transfer is performed. The method of inserting idle
cycles depends on the contents of DMAIWA.
00: No idle cycle inserted
01: 1 idle cycle inserted
10: 2 idle cycles inserted
11: 4 idle cycled inserted
Rev. 2.00, 09/03, page 156 of 690