User`s manual
XP890054 s Software Reference
Expansion Board Addresses
XP8900 Series
Up to eight XP8900 Series expansion boards may be addressed over a
single PLCBus using a logical address of 0 to 7.
The 12-bit address of a particular XP8900 is determined by the jumper
setting on header P3. P3 may be set eight different ways. The unique
physical address is in the form
0010 000x yzRR
where
x = 1 when P3 pins 12 are not connected
y = 1 when P3 pins 34 are not connected
z = 1 when P3 pins 56 are not connected
and RR is reserved for the registers. There are no PAL codes.
The 12-bit address can be placed on the bus using 4-bit addressing. The
functions set12adr, read12data, and write12data (in
DRIVERS.LIB) use 12-bit bus addresses.
When the address is passed to set12adr, it should be in the format
yzRR 000x 0010
where the least significant nibble in the physical address, yzRR, has
swapped places with the most significant nibble in the physical address,
0010.