Serial Control Commands - Promax MO-160 Manual De Usuario

9. Go back to the Com Port List tab. The new COM port is shown along with
additional information if available:
-
IP Address of the modulator to which the COM port is connected.
-
Status of the connection between the COM port and the MO-16X.
The virtual COM port is now set up and ready to access the modulator or
modulators connected to the subnetwork that will respond to its associated IP address.
It is possible to verify the status of a virtual serial connection using CPR Manager.
First of all, we have to double check that the modulator we are trying to talk to is turned
on and connected to the network.
Then from CPR Manager select the General Tests tab and open the COM port we
created. If everything is working all right, the counter of received characters Rx Data will
be increased by one for each character received from the modulator. For example, the
count will be incremented by one every time the MO-16X sends a XON code over the
virtual serial port (once per second).
If we cannot open the COM port and yet we believe that everything is properly
configured, we can do a ping from the MS-DOS command prompt (Windows Startup
menu -> Run -> cmd) to the IP address of the modulator. This will tell us whether the
MO-16X is really accessible through the Ethernet connection.
It might be the case that the modulator replies to a ping command but we are
unable to open the virtual COM port. It is worthwhile then to check whether this COM
port is being used by another programme. If not, a fallback plan consists in deleting the
COM port and starting from scratch.

4.12.3 Serial control commands

The virtual COM port created following the steps described in the previous section
can be used to remotely control the MO-16X using a computer. A suitable set of remote
control commands enables us to query and change most of the functionality of the
modulator using software that controls serial devices such as Windows Hyperterminal.
There is a control protocol to synchronise command reception and validation. A
command must be sent once an XON (ASCII 0x11 in hexadecimal) character is
received from the modulator. When the modulator detects a complete command, it
sends an XOF (0x13) code and, once validated and executed, an ACK (0x06) or NAK
(0x15) is sent back to the remote controller.
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USER'S MANUAL. MO-16X
04/2008