Advanced Instruments 4C3, User Manual

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3. Serial Communication Port (see figure 7): The serial port can
reliably communicate over shielded cable up to 10 meters in
length. Data is transmitted asynchronously as 1 start bit, 8 data
bits and 1 stop bit, with no parity. Hardware handshaking is
supported; XON-XOFF software handshaking may be selected
by means of the SETUP menu (see section K).
The default serial data rate is 1200 bps (bits per second), though
300 bps and 9600 bps may alternatively be selected (see section
K).
Each message transmitted from the communication port is ter-
minated by the sequence, Carriage Return (0D Hex), Line Feed
(0A Hex), Null (00 Hex). For display purposes, most messages
consist of less than 20 characters but longer messages, which
scroll across the display, are transmitted no differently.
The 4C3 transmits a significant amount of information via
the communication port. Almost every item of information
displayed by the instrument can be transmitted over the port,
including test results, all error messages, and most display data
from the TEST menu.
The serial communication port conforms to the DTE EIA-
232/V.24 (RS-232) standard and has one of the following pin
assignments:
13
Installation & Setup
Signal Pin Direction
Carrier Direct 1 to 4C3
Receive Data 2 to 4C3
Transmit Data 3 from 4C3
Data Terminal Ready 4 from 4C3
Signal Ground 5 common
Data Set Ready 6 to 4C3
Request to Send 7 from 4C3
Clear to Send 8 to 4C3
Table 2: Communication Port Connections