Toshiba TLCS-900/H1 Series Data Book page 100

3.6.3 Basic functions and register setting
In this section, setting of the block address area, the connecting memory and the number of
waits out of the memory controller's functions are described.
(1) Block address area specification
The block address area is specified by two registers.
The memory start address register(MSARn) sets the start address of the block address areas.
The memory controller compares between the register value and the address every bus cycles. The
address bit which is masked by the memory address mask register(MAMRn) is not compared by the
memory controller. The block address area size is determined by setting the memory address mask
register. The set value in the register is compared with the block address area on the bus. If the
compared result is a match, the memory controller sets the chip select signal(CSn) to "Low".
(i) Setting memory start address register
The MS23 to 16 bits of the memory start address register respectively correspond with
addresses A23 to A16. The lower start address A15 to 0 are always set to address 0000H.
Therefore the start address of the block address area are set to addresses 000000H to
FF0000H every 64K bytes.
(ii) Setting memory address mask registers
The memory address mask register sets whether an address bit is compared or not. Set the
register to "0" to compare, or to "1" not to compare.
The address bit to be set is depended on the block address area.
Block address area 0 : A20 to A8
Block address area 1 : A21 to A8
Block address area 2 to 3 : A22 to A15
The above-mentioned bits are always compared. The block address area size is determined by
the compared result.
The size to be set depending on the block address area is as follows.
Size (bytes)
256
CS area
CS0
○
CS1
○
CS2 to 3
Note: After reset release, only the control register of the block address area 2 is valid. The control
register of the block address area 2 has <B2M> bit. Setting <B2M> bit to "0" sets the block
address area 2 to addresses 000000H to FFFFFFH. Setting <B2M> bit to "1" specifies the
start address and the address area size as it is in the other block address area
512 32 K 64 K 128 K
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92CH21-96
256 K 512 K 1 M
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TMP92CH21
2 M 4 M 8 M
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