2. Accepting from a computer program and storing any combination of eight digital command signals and providing these signals to remote digital command transmission equipment synchcronuosly with a command PRF signal of up to 2 kb/s.

3. Routing the digital command PRF signal to the TT&C command transmitter.

4. Accepting and storing digital command echo check signals from the remote transmission equipment and providing these signals to the computer program.

5. Inhibiting command transmission; that is, when an error occurrs, the data handling equipment, in accordance with prior computer program instructions shall:
   1. Terminate Transmission or

   2. Ignore the error and continue, or

   3. Repeat the command, or

   4. Send S pulses.

The data processing configuration shall be capable of generating or providing the following status and control functions:

1. System time

2. Station time

3. Playback time control

4. Command verification

5. Digital command PRF

6. Vehicle time code word

7. Remote status

8. Remote control

9. Intersubsystem configuration

10. Station configuration

The data configuration shall be capable of accepting data from the computer program and of providing the data in serial format to external communications equipment for transmission to the STC. Similarly, it shall also be capable of accepting serial format data from the STC (sychronously with a data clock signal of up to 2400 b/s) and of providing this data to the computer program. The configuration shall be capable - when instructed by the computer program - of sychronously accepting and/or outputting data in 16- or 30-bit segments and accepting and/or outputting data in descrete frames as defined by corresponding input frame signals. The equipment under computer control shall be capable of providing up to six communications control signals to external communications equipment and of similarly accepting up to six status signals.

2.4    COMMUNICATIONS

Both intrastation and interstation communications shall be provided.

The intrastation capability shall provide for coordination and control of on-site activities via voice (public address) and telephone. The interstation capability shall provide for terminating data, teletype, and voice communications links to and from the STC.

2.4.1    Interstation Communications

Interstation communication facilities shall provide for termination of the following links to the STC:

1. Full duplex, secure, digital data links that provide exchange of data at a 2400 b/s rates. It shall be possible to multiplex tracking, command, and telemetry data for transmission on a single link. Provision shall be made for automatic sychronization between transmitting and receiving crypto devices.