SADL Radio and Interface Notes

Contents

  1. Computer Wiring Connections
  2. FORCES SADL interface files and directories
  3. FORCES SADL utility programs
  4. The RS232 (COM1 port) interface

Computer Wiring Connections
Refer to the Changing the SSE Configuration document on wiring connections to the radio.

The SADL radio and computer wiring has some variations that were put in place for development/testing purposes. As none of the testing connections work in a Live mode, their function is explained here to make clear when the connections are correct.

  1. SSE Computer
    The wire connected to the radio's DATA J3 port connects to the (only) DB25 connector on the back of the SSE computer (normally used as the paraller printer port). This is the connection that is used as the URO to initialize the radio.

    (the URO data-format is undocumented (Raytheon) and so JFORCES is unable to support/replace it. Note however that conversations with Dennis O'Donoghue/Raytheon in Oct 2003, indicate that a firmware/hardware upgrade of the radio scheduled for Sep 2004 release will eliminate the need for this connectivity. Once we've received the documentation, we can develop the RS232 initialization specification within JFORCES, then we will be able to retire the 'SSE computer')

  2. FORCES Computer
    The high-hat J2 connection on the back of the radio is wired with a "Y" cable. For Production use, one (either) DB9 end is dangled on the floor, while the other end is connected to the sadl/FORCES/linux computer's DB9 COM1 port. Physically, this is the top DB9 on the computer tower.

  3. Variations
    There are a number of wiring variations available for testing/debugging/development purposes. They are described here because if you leave them cabled this way, the SADL interface will not work live.

    1. If you connect the 2nd DB9 connector on the radio's "Y" cable to the SSE computer, SSE will completely 'drive' the radio, and JFORCES can only be a passive monitor. This is useful for verifying connectivity problems with aircraft (making sure it isn't a JFORCES problem).

    2. There is another short "Y" cable sitting on top of the FORCES computer (that is clearly homemade). This is used to monitor data transmitted from the SSE computer as well as from the radio. To install, connect the ('dangling') radio "Y" cable DB9 to the SSE computer. The other DB9 radio connector (normally connected to JFORCES' COM1 port) is connected to the male end DB9 of the "Y" cable on the JFORCES computer. The other ends plug into the JFORCES computer's COM1 and COM2 ports: the wire/connector labelled XMIT goes to the COM2 port (the lower DB9 connector on the computer tower).

      When you run the SADL interface, it will collect radio data as usual. To collect data transmitted by SSE, (additionally) run the JFORCES utility called:
      sse_interface

    When you are done testing, be sure to re-connect the cabling per 1. SSE Computer and 2. JFORCES Computer, or you will not get a working connection for the Live environment (notably, JFORCES will not be able to transmit)


SADL interface files and directories


FORCES SADL utility programs
  1. sadl_playback
    All data captured from the radio (theoretically being aircraft data) is stored in timestamped filenames as: /data/sadl/archives/sadl_yyyy_mmm_dd_hh_mm.hextime

    The data can be played back in FORCES by selecting Run SADL in Replay Mode from the Remote Interfaces, Start SADL Interface menu, and selecting a specific file.

    For detailed analysis of the data, you can run the command-line utility sadl_playback to dump a file. Recommended options are:
    > sadl_playback -1 -n filename
    -- dump the filename (note that you do NOT include the directory spec), using a brief output ('-1'), and don't sleep the realtime intervals ('-n') - just dump it straight out.
    > sadl_playback -3 -n filename
    -- dumps the filename in its entirety, including all fields in records with a known format, and a full hexdump of all records.

  2. sse_interface
    When you have the JFORCES computer wired to monitor the SSE computer's data transmits (ref: Computer Wiring Connections), the sse_interface program is used to monitor and record the data transmitted by the SSE computer. Just start the program from the command line:
    > sse_interface
    -- to start recording.

    It will display the filename it is recording to.
    It minimally parses the Raytheon-specific message wrapper. If the header isn't there, we aren't going to find valid SADL data inside it, so it doesn't record 'bad' data. It does however, output the bad data in printable format to stdout (the screen). Given that, you might want to pipe the sse_interface output to a logfile for later review (note that the only time the data has been 'bad', has been when the terminal/port baud rate was incorrect).

  3. sse_playback
    sse_playback is used to translate and display the sse_interface files (recordings of the SSE computer's transmits), as well as the sadl_send_* files (the JFORCES computer's transmits).

    Neither of these file-types have any Replay representation within the JFORCES mmi.

    Recommended options are:
    > sse_playback -1 -n filename
    -- dump the filename (note that you do NOT include the directory spec), using a brief output ('-1'), and don't sleep the realtime intervals ('-n') - just dump it straight out.
    > sse_playback -3 -n filename
    -- dumps the filename in its entirety, including all fields in records with a known format, and a full hexdump of all records.


The RS232 (COM1 port) interface

rev: 02-Dec-2003