Working with Serial Only Systems

    Some embedded systems (or retired commercial firewalls) do not have keyboard and VGA ports, but are fully controlled via the serial ports. For the most part, things work exactly the same. The differences are below...

    • You will need a terminal program. Hyperterm on Windows is the old classic. I have used gtkterm on Linux with no complaints.
    • You may need a "null modem" or "null modem cable" to connect to your hardware.
    • You will need to configure the BIOS from the serial port. At this point, SmallWall is not running, so the connection speed is totally up to the BIOS.
    • Yes, you can install the serial version on a standard PC with a serial port. But that will not give you serial access to the BIOS, nor will it bypass the check for a keyboard by the BIOS on boot.
    • Terminal speed can vary based on the hardware it is running on. Most times, it is the same as what the BIOS uses, but in some cases that information is not passed correctly. Try;
      • 9600 8n1
      • 19200 8n1
      • 38400 8n1
    • You can change from standard to serial and back again. But the system will alert that you are uploading a different type. Rename you image to the filename it expects to work around this.
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