Avago Technologies LSI53C1010 - Manual (Page 39)

Big and Little Endian Byte Addressing 2-9
2.5.2 Operating Register Access from Firmware
Developing code that works in either mode requires use of equates for
the register names, with an endian switch specified at compile time that
includes the appropriate set of address values. This change is only for
byte access. If 32 bits are accessed, there is no address change from
big to little endian.
2.5.3 Operating Register Access from SCRIPTS Routines
NASM uses logical names to access registers. Names do not change
when the mode changes, nor does the binary code required to access a
register.
2.5.4 User Data Byte Ordering
Data transfers between system memory and the SCSI bus always start
at the beginning address and continue until the last byte is sent. No
internal reordering of the data for either mode occurs. A serial stream of
data is assumed, and the first byte on the SCSI bus is associated with
the lowest address in system memory, regardless of the big or little
endian mode.