August 2012 – Ed.1.2
EQUITEL – E451 Technical manual
Page 18
Chapter 4
Auxiliary input and output control
In this chapter, we will explain how to read the auxiliary input and how to update the dry contact output
available in E451.
These contacts are physically accessible in some connectors, as described in the points 1.9 and 1.10 . Through
them it is possible to connect other external devices.
4.1
Contacts control commands
Contacts can be consulted and updated with the EQUITEL proprietary protocol, using the commands
described below and that are explained in detail in the “
EQUITEL E400 family communications protocol
”.
4.1.1.
Configuration consult
The two auxiliary contacts configuration is fixed and defined by its protection circuit (see points 1.9 and
1.10 ). The use of this command will send this configuration back to the controller.
1.
The controller may consult the auxiliary contacts configuration by sending the TCP command
“QRYPPORTCONFIG”.
2.
E451 sends the command “PPORTCONFIG” back, which includes the contacts address parameters
and their initial value.
4.1.2.
Output writing
According to the output contact electrical scheme (see Figure 6) there is a “normally open” relay. To
activate it, we will have to write “1”in pin dedicated to this output. In order to restore it to its original
status we will have to write a “0”.
1.
In order to remotely write the desired value over the pin configured as output, the controller
send the command “WRITEPPORT” followed by the desired parameter (
1
/
0
).
2.
E451 will answer with the corresponding ACK, in this case “ACK_WRITEPPORT”.
4.1.3.
Contacts reading
The input contact has to be “normally open” as described in the electrical scheme in Figure 5. In stand-by
mode, in the pin dedicated to this input a “1” will be read. Should the contact be activated, we will read a
“0”.
1.
The controller can consult the contacts value by sending the command “READPPORT”.
2.
In this case E451 will answer with the command “PPORT” followed by the parameter
corresponding to the input and output values.
4.1.4.
Change in the inputs status
1.
When the auxiliary input contact changes its status, E451 sends the command “CHANGEPPORT”
showing this change.
2.
The controller will answer with the corresponding ACK, in this case “ACK_CHANGEPPORT”.
4.2
Output contact activation by DTMF tones
The activation of the output relay can be controlled by DTMF tones generated with the SIP telephone with
which the communication has been made.
The relay activation time and the digits code are selectable through the web server.
The DTMF tones can be in- band (encoded as audio) our out-of-band through the signaling commands in SIP
or RTP using the mechanism RCF-2833.
