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Using DAD to Control the Unity 4000 Receiver

To use DAD as a control source for switching a port on the Unity 4000 (U4K), a text string needs to be sent to the terminal control port on the receiver. It is best to use serial port 1 on the receiver. This port is a true COM port and is buffered to receive information at higher speeds. Set up the U4K so that the hardware setup screen shows that the TERMINAL is at port 1, and is operating at 9600, N, 8, 1. (See the U4K operating manual for more detailed instructions.)

The control cable from the DAD to the U4K is a straight through cable (not a NULL MODEM cable.) The DAD only sends data to the U4K; it does not receive any data. The data sent is ASCII text data, and is sent as a text string.

There are two possible methods of sending control data to the U4K. One is switching the receiver and also switching an input switcher at the same time. The other is strictly switching the receiver. If there is no input switcher, and the U4K port is directly connected to a COM port of the DAD, then it still is possible to use a switcher function command to control the U4K. In this case you would need to make sure that the . CFG file for the workstation has the COM port you have connected to the U4K as the port you are using in your SWITCHER_IN_IO statement.

The command statements that follow assume that you have connected an input switcher, and are controlling the U4K as well.

DAD Configuration

Commands are sent as ASCII text strings to designated COM ports. This is done using SEND TEXT dcl commands issued from within DAD. You must configure the DAD so that it understands which port is connected to the desired device to be controlled. There are four possible channels available to send text data. You must assign COM port numbers to the text channels you wish to use in the DAD workstation .CFG file. This is configured using the SEND_TEXT_X_IO parameter, where X is text output channel A, B, C, or D.

As a matter of further discussion, you will need to make sure that the COMX_INFO, and SWITCHER_IN_IO statements are correct for the DAD workstation .CFG file. It would appear as follows for the switcher, assuming you are using a switcher on COM2:

   COM2_INFO                          = "2400 N 8 1"

   SEND_TEXT_B_IO               = 2

   SWITCHER_IN_IO              = 2

It would appear as follows for the U4K port, assuming that it is connected to COM3:

   COM3_INFO                         = "9600 N 8 1 NO"

   SEND_TEXT_A_IO              = 3

Switcher Commands

The switcher command file may include both switcher functions as well as DCL commands. The first command statement, at the top of the file, is the total number of switcher commands, or functions, that are listed. Switcher commands are made up of a series of labels to identify the commands.The label is enclosed in quotes. Following the label is a letter that identifies the type of contents to be executed. This letter identifies the command line as a Switcher serial string command, to be sent out the designated COM port, or a Command function that can be executed from the DAD if the labeled switcher function is executed. The command, or string contents, that follow the letter will be enclosed in quotes.

To switch the switcher and control the U4K in a single command, you need to use a switcher command function. You create the command much the same way you would create regular switcher commands, with the exception that it is a command statement and not a switcher control function. For example, a typical switcher control function statement might be as follows:

   "AA1" S "P56*22^MP56*E^M"

Where AA1 is the label that you would see in the switcher selection box, the S stating that the following command is a switcher function, with the following data to be sent out the designated switcher IO port designated in the SWITCHER_IN_IO of the .CFG file for the DAD workstation.

When using the switcher command function, you need to send two command strings. One goes to the switcher, the other goes to the U4K. For example, a typical switcher command statement, when using the previous configuration parameters, might be as follows:

   "SNN" C "SEND TEXT A '^MSETAUDIO 4 S SNN^M^M':SEND TEXT B 'P56*52^MP56*E^M' "

The command structure sends text data to the U4K out channel A, and text data to the switcher goes out channel B. In the previous example, you will notice that the data sent to the switcher is constructed in the same way as it is in the switcher function statement. The data sent to the U4K is as follows:

   ^M       -           is the DAD dcl equivalent to an ASCII CR

   SETAUDIO <port> <channel> <source>       -           U4K command statement

In the previous example, the first ^M clears the U4K command buffer. The SETAUDIO command is sent changing port 4 to stereo mode and to audio source SNN. The last two ^M signal the U4K to execute the command, and clear the command buffer.

It is worth noting that if you change a U4K port, using this method for a particular switcher input, that all labels for that input must be a command function. Do not mix control and command functions for a particular switcher input. For example, if you have labels such as:

   "AA1" S "P56*52^MP56*E^M"

   "SNN" C "SEND TEXT A '^MSETAUDIO 4 S SNN^M^M':SEND TEXT B 'P56*52^MP56*E^M' "

in your switcher file, going to SNN will be no problem. However, returning to AA1 after going to SNN will not give you the desired result. The switcher will switch to the correct input, but the audio will still be SNN. The correct method would be:

   "AA1" S "SEND TEXT A '^MSETAUDIO 4 S AA1^M^M':SEND TEXT B 'P56*52^MP56*E^M' "

   "SNN" C "SEND TEXT A '^MSETAUDIO 4 S SNN^M^M':SEND TEXT B 'P56*52^MP56*E^M' "