Specifications

54 PCI-Comm Card Series User's Manual

All Ports Stop stop test on all ports

Clear Message clear messages on Message Logo area and the Rx

length information on the Performance Listing

area

Each Com Port tab represents a specific port

you have selected for test and configuration.

On the tab, you can see the Transfer Mode,

Port Status, and Message Logo area.

Transfer Mode

You can specify the transfer mode to be

Normal, loopback (active) and loopback

(passive)

Normal—allows data to be transmitted

and received simultaneously. The data

receiving rate is helpful in identifying the

performance of communication card installed

on your system.

Loopback-loopback mode will transmit a series of special data,

which are expected to appear on the receive line. Using the loopback

mode, we can check the integrity of received data and find whether

any error occurred on the transmit line. The active loopback and

passive loopback must work in pair to enable the loopback mode.

When a port operates as active loopback mode, it will send data first

and receive data later. Another port, which operates as passive

loopback, will retransmit any received data on Rx line and then send

these data onto Tx line. These two modes will form a logical loop and

help to verify the integrity of data transmitted over the communica-

tion link.

DTR (data-terminal-ready)