Mitsubishi Electric MELSEC-A User Manual page 144

14. AJ71 UC24 MASTER STATION
MELSEC-A
IMPORTANT(
The data store procedure of the receive data area differs according to
the setting of the maximum number of transmission points (256 or 512).
When the maximum number of transmission points is set at 512, read
of higher
8
bits only of each address is disabled. It is necessary to
prepare a program that executes the FROM instruction every word and
then processes higher 8 bits only by use of the sequence program.