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Chapter 31 External Bus
2.External Bus Interface Registers
2. External Bus Interface Registers
This section explains the registers used in the external bus interface.
■ Register Types
The following registers are used by the external bus interface:
• Area select registers (ASR0-7)
• Area configuration registers (ACR0-7)
• Area wait registers (AWR0-7)
• Memory configuration register (MCRA for SDRAM/FCRAM auto - precharge OFF mode)
• Memory configuration register (MCRB for FCRAM auto - precharge ON mode)
• I/O wait registers for DMAC (IOWR0-3)
• Chip select enable register (CSER)
• Cache enable register (CHER)
• Pin/timing control register (TCR)
• Mode register (MODR)
2.1 Area Select Registers 0-7(ASR0-7)
This section explains the configuration and functions of area select registers 0-7 (ASR0-7).
■ Configuration of area select registers 0-7 (ASR0-7)
The area select registers (ASR0-7: Area Select Registers 0-7) specify the start address of each chip select area
of CS0-CS7.
Figure 2-1 "Configuration of the Area Select Registers (ASR0-7)" shows the configuration of area select registers
0-7 (ASR0-7: Area Select Register).
