TCG140_R1.1 – May 2018
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<URL> is a valid URL to public server, pointing update (.cod) file
Example
Command:
update www.teracomsystems.com/docs/TCG140-v1.000-P-S.cod
Answer 1:
Downloading firmware...
Answer 2:
Firmware file downloaded. Updating...
Following answers are also possible in different situations:
Answer:
File corrupt or wrong version!
Answer:
Can't connect to server!
Answer:
Download time out!
Answer:
GPRS is not connected!
Answer:
Connection lost!
Answer:
Response timeout!
Answer:
Socket error!
9.
HTTP API
HTTP is a very popular protocol for implementation of remote monitoring and control SCADA systems.
These systems are built on the client-server technology.
TCG140 supports both - client mode (HTTP Post) and server mode (HTTP Get). This makes the device
compatible with all SCADA software running HTTP protocol.
9.1.
HTTP Post
The HTTP Post service is used when TCG140 utilizes a data card that has no fixed public address.
In this case, the controller has an internal IP address from the network of the mobile operator
and can’t be accessed via the Internet.
If the service is active, the controller periodically sends the HTTP Post to a server. This post
contains an XML/JSON file with the current status of monitored parameters.
The post can be sent also on an alarm condition - there is an analogy with SNMP trap.
On every HTTP Post, the server returns command or FIN to terminate the connection.
A very important parameter in this communication is the HTTP Post period. With shorter time
period the device generates more data traffic, but this keeps the information and possibility to
control the device closer to "real-time".
The HTTP Post period can be changed by the server with appropriate HTTP command. This makes
the communication very flexible.
Below is a typical communication session between TCG140 and remote server:
Summary of Contents for TCG140
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