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MOAS Server

Rotators

MOAS Rotator

Section titled “MOAS Rotator”

The MOAS Rotator program communicates with the MOAS Server and with antenna rotators connected to serial or USB ports. It has no configuration file. Instead all configuration information is provided by the MOAS Server. The program must be run on any computer that has rotators connected. It can be run on any number of computers. The MOAS Server configuration tells the server which computers are running the program.

graph LR
    subgraph PC1[Computer]
        SVR[MOAS Server]
        MR1[MOAS Rotator]
    end
    subgraph PC2[Computer]
        MR2[MOAS Rotator]
    end
    SVR --> MR1
    SVR --> MR2
    MR1 --> ROT1[Rotator 1]
    MR1 --> ROT2[Rotator 2]
    MR2 --> ROT3[Rotator 3]

There is no practical limit on the number of computers running MOAS Rotator or on how many rotators are connected to each computer.

The following rotators are supported:

Model NameRotator Information
DCU1Hy-Gain DCU-1. This rotator does not provide position information.
YaesuYaesu GS-232A or GS-232B. Also used by other vendors.
RotorEZRotorEZ (enhanced DCU-1 protocol). Used by Green Heron and others.
RC2800P-AM2 RC2800P-A.
RC2800P-XM2 RC2800P-X.
AlfaspidAlfaspid ROT1.
Prosistel DProsistel with model D controller.

Other rotators will be supported in the future.

If the Address of a rotator is not specified, the default is that it is on the same PC as the server. This is equivalent to specifying 127.0.0.1 as the address.

The Poll time controls how often the MOAS rotator checks the rotator position. The time is in milliseconds. A shorter time will make the rotator indicators less “jumpy”. Normal values would be 1000 or 2000. Some rotators such as the RC2800P-A send direction information whenever it changes. The poll time is ignored for these rotators.

The MOAS Rotator program is started by the MOAS Server on the PC where the MOAS Server is running if any rotators are configured which use it. This behaviour can be disabled in the configuration by setting StartMOASRotator to false.

The MOAS Rotator program must be started manually on other computers which have rotators attached.

Protocol

Section titled “Protocol”

The MOAS Server connects to the MOAS rotator using TCP/IP on port 13020. This port number cannot be changed.

The server sends text commands using 8-bit ASCII. The commands are terminated with a carriage return character. If a command has multiple fields they are separated by a single space.

Commands sent by the MOAS Server

Section titled “Commands sent by the MOAS Server”
  • VERSION Send the version number of the MOAS rotator.
  • CONFIGURE <rotator> <port> <model> <poll> Configure a rotator.
    • <rotator> is a number the server has assigned to this rotator.
    • <port> is the name of the port. It usually starts with COM, for example COM14.
    • <model> is a number representing the model. Currently implemented: DCU1=1, RotorEZ=2, Yaesu=4, Alfaspid=5, and RC2800P-A=8. Some other numbers are reserved.
    • <poll> is the polling time in milliseconds. It is always included, even if the rotator ignores it.
    • Example: CONFIGURE 0 2 COM14 2000
  • ROTATE <rotator> <degrees> Turn a rotator.
    • <rotator> is a number the server has assigned to this rotator.
    • <degrees> is the direction to turn in degrees. For most rotators this is the number of degrees clockwise from the counterclockwise stop.
  • STOP <rotator> Stop turning a rotator.
    • <rotator> is a number the server has assigned to this rotator.

Messages sent by the MOAS Rotator program

Section titled “Messages sent by the MOAS Rotator program”
  • VERSION <version>
    • <version> is a string in the form <major>.<minor> where <major> and <minor> are numbers.
  • <rotator> <degrees>
    • The current heading for a rotator. This is sent whenever the MOAS Rotator program notices that the rotator has changed direction.
    • <rotator> is a number the server has assigned to this rotator.
    • <degrees> is the current heading of the rotator.