User's Manual

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E Series Data Radio – User Manual

Stream Setup

This button brings up a dialogue box to permit editing of Stream

IDentiﬁer (SID) codes which are used by the modem as the

addressing mechanism for data stream routing. A SID code can be

placed at the start of each data frame as it is sent over the radio

channel. The receiving modems use this code to determine how

to route the data message. The modem supports simultaneous

operation of both Port “A” and Port “B” over the one radio link,

along with the inclusion of a diagnostics data stream.

Each port is independent and supports multiple options which are

described in the following sections.

The following diagram illustrates the structure of the stream routing

function for each data port.

User Port

This option is selected by clicking on the User Port button and

ﬁlling in the RXSID and TXSID ﬁelds to the right. The radio comes

preconﬁgured with default values.

In User Port mode all SID code operations are performed

transparently to the user data. Data placed into a user port which

has been assigned a speciﬁed SID code, will only be received by

a modem at the other end of the radio link that has a user port

assigned with the same SID code. The SID code is added by the

radio modem to the user data stream and removed by the radio

modem when user data is outputted to a data port.

In this way, Port “A” and Port “B” can be assigned different SID

codes, thereby separating the data streams.

Two SID codes values are available for each user port RXSID and

TXSID. The RXSID codes apply to the data being received by the

modem, and the TXSID codes apply to the data being transmitted

by the modem. This allows for different transmit and receive codes

if required, but generally they would be both the same.

A situation where Tx and Rx SID codes may be different is in

a repeater conﬁguration. In this type of application all data

messages sent to the repeater will be “repeated”. Thus by having

different Tx and Rx codes, a control unit will not “hear” its own

transmission, and remotes will not hear the reply from any other

remote. For more information please consult the Trio E Series

training material available as a power point slide from our website

at www.trio.com.au

The diagnostics facility (when installed) also uses SID codes. The

diagnostics data simply uses a different data stream to the user

data, but is processed internally by the modem. If access to the

diagnostics facility is required, similar to when the diagnostics utility

is used with the modem, then the data port concerned and the

diagnostics stream, must have the same SID codes assigned to

them. Alternatively the System port can be used, which is 19.2K,

Slip.

Trunk Streams

In the Trunk Streams mode, data that is inputted into the modem

for transmission must have a SID code appended to the start of the

data packet. This mode requires the use of a “SLIP” interface as

conﬁgured using the packet layer.

Trunk Steam mode is normally used in conjunction with Trio

Diagnostics software, when connection to a MSR Stream Router

or when connecting radios together such as a back-to-back

connections as used in multiple point to point links.

In Trunk Stream mode a range of SID codes can be transmitted

and received via a data port. This range is speciﬁed when this

mode is selected. In a typical application, such as a back to back

connection as used in a multiple point to point links, where all

data (including diagnostics) from one radio needs to be “trunked”

through to the other radio, the range used is 0 to 255. Trunked

mode allows a conﬁgurable selection of data streams to be

“trunked” to other equipment yet the data remains separated as the

SID codes are appended to each packet of data outputted.

require this method of activation.

PTT Timeout

The PTT timeout facility is used to disable the transmitter if it

exceeds the designated time. The timeout value can range from 1

to 255 seconds and the facility is disabled by setting a zero value.

The timeout value chosen for this should be set according to

system requirements which may include:

• Prevention of a remote unit remaining keyed up and locking

out all other remote units in a point to multipoint system.

• Limiting the period a remote unit remains keyed up to

prevent battery drain in a low power application.

Note: If a PTT timeout occurs before completion of a data

transmission data will be lost.

Part I – TVIEW+ Management Suite - Programmer