The software configuration files are named with the
.bit extension. The bit file can be downloaded via
the Internet, from the ComBlock CD or any other
local file.
The option and revision for the software currently
running within the FPGA are listed at the bottom of
the advanced settings window.
Two firmware options are available for this
receiver:
-A
firmware uses an internal VCTCXO frequency
reference.
-B
firmware option requires an external 10 MHz
frequency reference.
Recovery
This module is protected against corruption by an
invalid FPGA configuration file (during firmware
upgrade for example) or an invalid user
configuration. To recover from such occurrence,
connect a jumper in J3 and during power-up. This
prevents the FPGA configuration and restore USB
communication [LAN communication is restored
only if the IP address is known/defined for the
personality index selected as default]. Once this is
done, the user can safely re-load a valid FPGA
configuration file into flash memory using the
ComBlock Control Center.
UDP Reset
Port 1029 is open as a UDP receive-only port. This
port serves a single purpose: being able to reset the
modem (and therefore the TCP-IP connection)
gracefully. This feature is intended to remedy a
common practical problem: it is a common
occurrence for one side of a TCP-IP connection to
end abnormally without the other side knowing that
the connection is broken (for example when a client
‘crashes’). In this case, new connections cannot be
established without first closing the previous ones.
The problem is particularly acute when the COM-
1826 is at a remote location.
The command “@001RST<CR><LF>” sent as a
UDP packet to this port will reset all TCP-IP
connections within the COM-1826.
TCP-IP connections can also be cleared remotely
from the ComBlock Control Center as illustrated
below:
17