Fujitsu FR60 Hardware Manual page 171

CHAPTER 4 EXTERNAL BUS INTERFACE
■ Functions of Bits in the Area Select Registers (ASR0 to ASR7)
The area select registers (ASR0 to ASR7) specify the start address of each chip select area
(CS0 to CS7).
The start address can be set in the high-order 16 bits (bits A31 to A16). Each chip select area
starts with the address set in this register and covers the range set by the four bits ASZ3 to
ASZ0 of the ACR0 to ACR7 registers.
The boundary of each chip select area obeys the setting of the four bits ASZ3 to ASZ0 of the
ACR0 to ACR7 registers. For example, if an area of 1 Mbyte is set by the four bits ASZ3 to
ASZ0, the low-order four bits of the ASR0 to ASR7 registers are ignored and only bits A31 to
A20 are valid.
The ASR0 register is initialized to 0000 by INIT and RST. ASR1 to ASR7 are not initialized by
H
INIT and RST, and are therefore undefined. After starting chip operation, be sure to set the
corresponding ASR register before enabling each chip select area with the CSER register.
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