Document 1-0479-013 Rev B
26
(6) Slave Security
With option 6 the user may disable the transceiver’s security so it will accept a call from any
other AutoWAVE unit. The default setting is 0 where security is enforced (the caller’s ID
number must be in the slave’s Call Book), with a setting of 1 security is disabled
As mentioned in mode 6, slave Security must be set to 1 when the unit is operating in a
Point-to-Point system where it may need to accept calls from more than 10 different
AutoWAVE transceivers. However, it is important to note that when Slave Security is set
to 1 the transceiver will accept calls from any other AutoWAVE transceiver, and additional
system security measures should be taken to prevent unauthorized access.
(7) RTS to CTS
Menu selection 7 in the Radio Parameters provides the option of allowing the RTS line
(pin 7) on the master transceiver to control the CTS line (pin 8) of the slave. This pass-
through control can be enabled in Point-to-Point mode as well as Point-to-Multipoint. In the
latter the Master RTS line will control all slaves’ CTS lines. When this mode is enabled the
CTS line ceases to function as flow control. Therefore it is not recommended to enable this
feature when operating at RS-232 speeds above 38.4 Kbaud..
To enable this mode, enter 7 in the Radio Parameters menu. An entry of 1 will enable the
RTS-CTS control, 0 will disable it.
Just before the time the master is scheduled to transmit a packet, it will sense the state of the
RTS line. If the state has changed, the master will then transmit a message to the slave with
the new status. This transmission will occur regardless of data to be sent or not. In the
former case the RTS status message will be sent in addition to the data. In Point-to-Point
mode the master will continue sending the new status message until it receives an
acknowledgment from the slave. In Point-to-Multipoint mode the master will repeat the
message the number of times equal to the Master Packet Repeat number in the Multipoint
Setup menu.
Because the master transmit time is completely asynchronous to the occurrence of any
change of the RTS line, the latency time from RTS to CTS is variable. The maximum time,
however is determined by the frequency of master transmission times. This frequency is
determined by the Maximum Packet Size and Minimum Packet Size parameters in the Radio
Parameter menu. Setting both parameters to their maximum of 9 and 9 will produce a
maximum latency time of approximately 25 mS. At their minimum numbers the time will
be approximately 10 mS. Please note that this latency can go up significantly if packets are
lost between the master and slave. In Point-to-Multipoint mode there is no absolute
guarantee that the state change will be communicated to all slaves in the unlikely event that
all repeated packets from the master do not get through to all slaves.
