SNR016

16M-bit Mask ROM

4. MEMORY MAPPING

For 8-bit AD (address/data) bus interface, all the address and data communication

between SNC710 and SNR016 are through data bus D[0..7]. SNC710 allows user to

connect maximum 2 external mask ROM, and SNR016 has 4 bank select pins

(BS1~BS4) to specify the memory region of each mask ROM.

BS4~BS1

Address Region

0010

0x0200000 ~ 0x02FFFFF

0011

0x0300000 ~ 0x03FFFFF

0100

0x0400000 ~ 0x04FFFFF

0101

0x0500000 ~ 0x05FFFFF

0110

0x0600000 ~ 0x06FFFFF

0111

0x0700000 ~ 0x07FFFFF

1000

0x0800000 ~ 0x08FFFFF

1001

0x0900000 ~ 0x09FFFFF

1010

0x0A00000 ~ 0x0AFFFFF

1011

0x0B00000 ~ 0x0BFFFFF

1100

0x0C00000 ~ 0x0CFFFFF

1101

0x0D00000 ~ 0x0DFFFFF

1110

0x0E00000 ~ 0x0EFFFFF

1111

0x0F00000 ~ 0x0FFFFFF

Table-1

Note: For the address region 0x00000~0x01FFFFF are reserved, and the setting

of bank select pins BS4~BS1 CAN’T be the range 0000~0x0001.

Ver. 1.4

October 21, 2005

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