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How to set bus width for data multiplex I/O space to specify the 14-bit?

Latest Updated:03/25/2009

Question:

The hardware manual says that the bus width for address/data multiplex I/O space is selected on A14-bit, and it is 8-bit when A14=0, and it is 16-bit when A14=1. How should I set it to specify the 14-bit? 

Answer:

The bus width for address/data multiplex I/O space selects the 8-bit bus width or 16-bit bus width according to accessed addresses.
(The example for SH7045)
Address/data multiplex I/O space is CS3 space (H'00C00000~H'00FFFFFF). In this space, the space of A14-bit=0 is 8-bit bus width and the space for 14 bit=1 is 16 bit bus width.
Each address space is shown as follows.
•Space for 8-bit bus width:Address low 16 bits are H'0000~H'3FFF, H'8000~H'BFFF
•Space for 16-bit bus width:Address low 16 bits are H'4000~H'7FFF, H'C000~H'FFFF
Suitable Products
SH7065
SH7040, SH7041, SH7042, SH7043, SH7044, SH7045
SH7014, SH7016, SH7017