User Manual

MHX-920 Operating Manual: Chapter 4 Configuration 33
S Register 118 - Roaming
This mode is activated on slaves and repeaters by setting register S118=1.
In this mode, a slave/repeater looks for synchronization with a Master
having the same network address and encryption key, but without regard for
the hopping pattern S106. Once the slave/repeater finds such a master, it
tunes to that master’s hopping pattern. If synchronization is lost, the
slave/repeater will again begin searching for a new master. Using this
algorithm, a mobile unit can ‘roam’ and automatically synchronize with a
new master once it loses communication with the previous one. It is
essential that all Masters with which a roaming slave/repeater will be
communicating with use a hopping pattern from within the same group. See
Appendix F. The allowable settings for this register are:
*0 Disabled
1 Enabled
S Register 119 - Quick Enter to Command
By setting this register to 1, a delay of 5 seconds is introduced at power-up
before the modem goes into data mode. If, during these 5 seconds, the user
enters ‘mhx’ the modem will instead go into Command Mode, and reply
with ‘OK’. The terminal baud rate must be set to 9600 baud. If an incorrect
character is entered, the modem will immediately go into Data Mode. The
default setting is 1 - Enabled.
S Register 120 - RTS/DCD Framing
S Register 121 - DCD Timeout
The MHX-920 supports two special types of data framing:
• Input (or RTS/CTS) Data Framing; and,
• Output (or DCD) Data Framing
Input Data Framing is enabled by configuring the Handshaking Parameter as
&K2. This type of framing makes use of the S120 parameter as illustrated
in Figure 9. Parameter S120 can be set to any value between 0 and 254 ms.
RTS
CTS
TXD
S120 (ms)
Data going into MHX-910
0 to 1 ms
Figure 9 - Input Data Framing