Sundance Spas ST201 - Manual (Page 84)

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Sundance Technology ST201 PRELIMINARY draft 2
EXPROMADDR
Class....................I/O Registers, External Interface Control
Base Address ......IoBaseAddress register value
Address Offset .....0x40
Access Mode .......Read/Write
Width ...................32 bits
ExpRomAddr holds the address to be used for direct I/O accesses of the Expansion ROM through the
ExpRomData port. To access a byte in the Expansion ROM, write the address of the byte to be accessed
into ExpRomAddr. Then issue either a read or a write to ExpRomData. For reads, the ROM value will be
returned by the read instruction. For writes, the new value will be programmed into the ROM upon comple-
tion of the write instruction.
BIT BIT NAME BIT DESCRIPTION
15..0 ExpRomAddr Address used for accessing expansion ROM.
31..16 Reserved Reserved for future use. Should be set to 0.