Oki MSM9225B, User Manual

Page: 43 / 92

MSM9225B User’s Manual
Chapter 2 Register Descriptions
2 – 30
2.4.7 Group Message Register (GMR0: 3Ehex, GMR1: 3Fhex)
These are registers to set the group message function.
Group Message Function
If the group message function is used, a part of an identifier can be masked. This can increase the
number of receivable identifiers.
To use the group message function, set the message box number of the target message box to set the
group message function in the GMR register. Then set the bits to be masked in the GMSK register.
If a received message corresponds to both a message box for which the group message function is
specified and a message box for which that is not specified, the message will be received in the
message box for which the group message function is not specified.
If the identifier of received message fits with the identifier of both group messages, the received
message will be written to the message box whose identifier (unmasked identifier set in the
identifier field) has the high priority.
The group message function can be set for two message boxes.
The group message function is valid when the EGM0/EGM1 bit is “1”.
Using GMR03 to GMR00 and GMR13 to GMR10, set the message box numbers of the message boxes for
which the group message function is to be set.
The numbers of the message boxes for which the group message function is to be set must be specified in the
descending order of box numbers in the range of message box numbers that correspond to the message box
count predetermined by the message box count setting register (NMES: 1Ehex).
If any message box numbers outside that range are specified, all bits in GMR0 and GMR1 are set to “0”.
At reset, all bits are set to “0”. (See Figure 2-31.)
The bit configuration is as follows:
MSB
EGM0
Not
used
Not
used
Not
used
GMR03 GMR02 GMR01 GMR00
LSB GMR0 (3Ehex), R/W: R/W
Initial
value:
0 0 0 0 0 0 0 0
MSB
EGM1
Not
used
Not
used
Not
used
GMR13 GMR12 GMR11 GMR10
LSB GMR1 (3Fhex), R/W: R/W
Initial
value:
0 0 0 0 0 0 0 0
Write a “0” to the unused bits.
Figure 2-29 Group Message Register (GMR0, GMR1)
B