Microhard Systems MHX-900, Operating Manual

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MHX-900 Operating Manual: Chapter 3 Configuration Options
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S Register 113 - Retry Limit
This setting has a range of 0 to 255, and determines the number of attempts
that will be made to retransmit data which failed the CRC checksum. Once
the limit is reached, the modem will give up and discard the data. If the
wireless connection is poor and data often needs to be retransmitted, a
modem could be “tied up” trying to retransmit, thus holding up pending
data.
S Registers 111 to 115 - Packet Parameters - Point-to-
Multipoint Mode
If the Operating Mode is Slave - Point-to-Multipoint, the default values for
the S registers are:
S111 Minimum Size (not used)
S112 Maximum Size (not used)
S113 Retry Limit 4
S115 Repeat Interval 8
In Master - Point-to-Multipoint mode, the default values for the S registers
are:
S111 Minimum Size 0
S112 Maximum Size 255
S113 Retransmissions 255
S114 Address Header Disabled
S Register 111 - Minimum Size
The Minimum Size parameter prevents the Slave from sending data until it
has buffered a minimum number of bytes. The Master determines this
parameter and passes the information to all Slaves in a Multipoint system.
S Register 112 - Maximum Size
Packet sizes in excess of the minimum size are limited by the Maximum
Size parameter. If the Slave is sending more than the minimum, the unit will
wait until it has buffered the maximum packet size or until a packet timeout
of two characters occurs on the serial port. The Master unit tells all Slaves
which maximum and minimum packet values to use. In addition, the Master
tells all Slaves which Hopping Interval to use (see Section 3.11).
S Register 113 - Retry Limit (Slave Point to
Multipoint)
Similar to the Retry Limit in Point-to-Point, the Slaves in a multipoint
system will reattempt to send a packet of data until it receives an
acknowledge or until it reaches the Retry Limit.