USER-PAK Option

Chapter 6
Creating Custom Serial Port Messages
6 – 9
The Buffer: No wait setting imposes a message size restriction. Due to
the size of the internal buffer, the combined length of all serial messages
to be transmitted for a single inspection must be no greater than 128
bytes; serial messages with a combined length greater than 128 bytes will
not be transmitted when Buffer: No wait is selected.
With Buffer: No wait selected, when a trigger is received, the Color
CVIM processes all of the strings defined for a serial port; if the content
of all serial messages to be transmitted does not fit into the buffer (either
the message is greater than 128 bytes, or the buffer is not completely
empty yet) the message is immediately discarded.
Note: The serial messages are always transmitted in full, or not at all – a
message is never partially transmitted.
The advantage to selecting Buffer: No wait is that no triggers are ever
rejected due to transmission of your custom serial port messages
(however, regardless of the Buffer: box setting, processing of serial port
strings does impact the Color CVIM inspection analysis time).
Disadvantages are that the total combined length of all serial messages to
be transmitted for a single inspection must be limited to 128 bytes or less,
and that, even if messages are so limited, some serial messages may not
be sent if the buffer has not had time to clear.
If you discover that you are missing messages with Buffer: No wait
selected, try using a higher baud rate, and/or shortening the length of
transmitted messages (limiting total combined serial message length for
each inspection to 128 bytes maximum). If this does not bring the desired
results, you may then want to consider using the Buffer: Wait setting.
Before the Color CVIM module can communicate through the serial
(RS-232) port to another device, the Color CVIM module and the other
device must be connected through a suitable communication cable, and the
communications parameters for the serial ports of both devices must match.
Selecting Serial Port Parameters
In order to use a serial port for serial messages, you must configure the serial
port for ASCII protocol, and you must select the baud rate to match that of
the connected device.
To select port parameters, with the Main menu displayed:
• Pick the Envir/Cam → I/O boxes to open the I/O menu.
RS-232 Port Connections
and Configuration