Comtrol RocketPort Universal PCI - Manual (Page 27)

RocketPort Universal PCI User Guide: 2000284 Rev. G Troubleshooting - 27
Troubleshooting
3. If the RocketPort Universal PCI is communicating with the device driver for
Windows, Port Monitor should display CLOSED status. If a port is open for an
application, it displays as OPEN, and displays Actual Throughput, TxTotal and
RxTotal statistics.
Normally, there should be no data errors recorded or they should be very
small. To find out what the actual errors are, scroll to the right. You will see
three columns: Overrun Errors, Framing Errors, and Parity Errors.
If the errors are:
• Overrun Errors represent receive buffer overflow errors. If this is the case,
you will have to configure either software or hardware handshaking to
control the flow of data. The most common errors are Overrun errors.
• Framing Errors indicate that there is an synchronization error between the
beginning of a data frame and the end of the data frame. A frame usually
consists of a start bit, 8 data bits, and a stop bit or two. The framing error
occurs if the stop bit is not detected or it occurs in the wrong time frame.
Most causes for framing errors are electrical noise on the data lines, or
differences in the data clocks of the RocketPort Universal PCI and the
connected device.
• Parity Errors occur when parity is used and the parity bit is not what is
expected. This can also be caused by noise on the data lines.
4. You can view additional statistics to Port Monitor by adding columns. Click
Tools and Add Columns.