Rs-232 Data Frame Format; Connection To A Computer Or Terminal - Agilent Technologies 34420A User Manual

Chapter 4 Remote Interface Reference
RS-232 Interface Configuration

RS-232 Data Frame Format

A character frame consists of all the transmitted bits that make up a
single character. The frame is defined as the characters from the start bit
to the last stop bit, inclusively. Within the frame, you can select the baud
rate, number of data bits, and parity type. The meter uses the following
frame formats for seven and eight data bits.

Connection to a Computer or Terminal

To connect the meter to a computer or terminal, you must have the
proper interface cable. Most computers and terminal are DTE (Data
Terminal Equipment) devices. Since the meter is also a DTE device, you
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must use a DTE-to-DTE interface cable. These cables are also called
null-modem, modem-eliminator, or crossover cables.
The interface cable must also have the proper connector on each end and the
internal wiring must be correct. Connectors typically have 9 pins (DB-9
connector) or 25 pins (DB-25 connector) with a "male" or "female" pin
configuration. A male connector has pins inside the connector shell and a
female connector has holes inside the connector shell.
If you cannot find the correct cable for your configuration, you may have to
use a wiring adapter. If you are using a DTE-to-DTE cable, make sure the
adapter is a "straight-through" type. Typical adapters include gender
changers, null-modem adapters, and DB-9 to DB-25 adapters.
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