New article Working with GSM Modem from an MQL5 Expert Advisor has been published at mql5.com:
There is currently a fair number of means
for a comfortable remote monitoring of a trading account: mobile
terminals, push notifications, working with ICQ. But it all requires
Internet connection. This article describes the process of creating an
Expert Advisor that will allow you to stay in touch with your trading
terminal even when mobile Internet is not available, through calls and
text messaging. In addition, this Expert Advisor will be able to notify
you of the lost or reestablished connection with the trade server.
For this purpose, virtually any GSM
modem, as well as most phones with the modem function would do. For
illustration, I have chosen Huawei E1550, as this modem is one of
the most widely used devices of its kind. Further, at the end of the
article, we will try to replace the modem with an old cellphone Siemens M55 (released in 2003) and see what happens.
But first, a few words on how to send a byte of data from an Expert Advisor to a modem.
Upon connecting the modem to your computer and installing all the
necessary drivers, you will be able to see a virtual COM port in the
system. All future operations with the modem are performed via this
port. Consequently, in order to exchange data with the modem, you should
first get access to the COM port.
Fig. 1. Huawei modem is connected to the COM3 port
Here, we will need a DLL library TrComPort.dll which is freely distributed in the Internet together with the source files.
It will be used to configure the COM port, query its state, as well as
to receive and send data. In order to get that done, we will use the
Author: Sergey Shevchuk