Chapter 5 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 bits 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 instrument uses the following frame formats for seven and eight data bits.

Parity:

EVEN, ODD

Start

Bit

7 Data Bits

Parity Stop Bit Bit

Parity:

NONE

Start

Bit

8 Data Bits

Stop

Bit

Connection to a Computer or Terminal

To connect the instrument to a computer or terminal, you must have the proper interface cable. Most computers and terminals are DTE (Data Terminal Equipment) devices. Since the instrument is also a DTE device, you 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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Agilent Technologies 34970A manual RS-232 Data Frame Format, Connection to a Computer or Terminal

34970A specifications

Agilent Technologies 34970A is a versatile data acquisition and measurement system that has gained popularity in various industries, including research and development, manufacturing, and education. The primary purpose of the 34970A is to offer an efficient solution for data collection, monitoring, and analysis, which can significantly enhance productivity and accuracy in testing applications.

One of the main features of the 34970A is its modular design, allowing users to customize the system according to their specific measurement needs. The mainframe can accommodate up to three plug-in measurement modules, which can include various types of measurements such as analog, digital, temperature, and frequency. This modularity provides flexibility for users to tailor the system to their requirements, making it highly adaptable to different applications.

Another notable characteristic of the Agilent 34970A is its impressive channel configuration. The system can support up to 120 measurement channels when fully configured, enabling extensive data acquisition without the need for multiple devices. This capability is essential for applications requiring simultaneous monitoring of multiple parameters or locations.

The 34970A utilizes advanced signal processing technologies to ensure high-accuracy measurements. The internal 6.5-digit resolution multimeter provides precise readings, while the device also supports various input types, such as thermocouples and RTDs for temperature measurements. The ability to perform mathematical functions, such as summation and averaging, on the acquired data further enhances its usability.

For data storage and management, the Agilent 34970A features built-in memory for storing up to 20,000 readings. Users can also easily transfer data to a PC through the RS-232 interface or GPIB (IEEE 488) for further analysis and reporting. Additionally, it offers the capability to program automatic data logging and scheduling of measurements, which streamlines the testing process and reduces manual intervention.

In terms of user interface, the 34970A is equipped with a large graphical display that provides clear visualization of measurement data and easy navigation through settings and options. The menu-driven interface makes it accessible for users of all skill levels, simplifying the setup and operation of the device.

Overall, the Agilent Technologies 34970A stands out for its modularity, high channel capacity, advanced measurement technologies, and user-friendly interface. As a reliable and efficient data acquisition system, it is well-suited for a wide range of applications, making it an essential tool for engineers and technicians looking to enhance measurement precision and efficiency.