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Analysis Mode

3.4

Configuration

To enter Configuration mode, press the PARM buttons simultaneously. The four buttons then assume the

functions shown in the CONFIG box. To exit Configuration mode, press the PARM buttons simultaneously

again. This operation does not cause parameters to be adjusted; only button releases are detected in

Configuration mode.

Configuration mode contains a number of adjustable parameters. To scroll through the available

parameters, use the VALUE buttons. To change the parameter values, use the PARM buttons.

Some items in Configuration mode are not parameters, but commands or gateways to a submenu. These

items are labelled as words with a question mark. To enter these items or to execute the command, press

either PARM button.

Although a few of the parameters in the Analysis and Scale configuration menus are the same, the

settings are kept separate between the modes. For example, input channel 1 can be selected in Scale

mode while input channel 2 is selected in Analysis mode. In this setup, when the ADS1232REF switches

from Scale to Analysis mode, the input channel becomes 2.

Table 5 summarizes the available parameters.

Table 5. Parameters in Analysis Mode

PARAMETER

DISPLAY

VALUE RANGE

DESCRIPTION

Averages

AVG=

2

–128

Number of points for average,

peak-to-peak, and RMS modes

Voltage Reference

VREF=

0.5

–5.0

Voltage used in various

calculations

Power-down mode

PDWN?

—

Power-down mode; see text

Offset calibration

OCAL?

—

Offset calibration; see text

Save parameters

SAVE?

—

Save parameters; see text

Version number

V1.1.0

—

Firmware version number display

3.4.1

Parameters

Averages: Number of points to use in Averaged, RMS noise, and Peak-Peak calculations. The choices

available are 2, 4, 8, 10, 16, 32, 50, 64, 100, and 128. The default setting is 50.

Voltage reference: To convert voltages to codes, the ADS1232REF requires the voltage reference level.

Since this level cannot be measured, it must be selected manually. This parameter allows the reference

level to be set.

Each digit of the voltage reference is selected and adjusted separately. Use the VALUE buttons to select

a digit, and the PARM buttons to adjust it. The selected digit flashes.

This parameter does not affect the actual voltage reference used. If it is incorrect, voltage calculations will

be wrong. The voltage reference is typically the +5V rail; the default value for this parameter is 5.0V.

Power-down mode: When either PARM button is pressed on this screen, the ADS1232REF causes the

ADS1232 to enter power-down mode. This action occurs by pulling the PDWN line low. While the PDWN

line is low, the display reads POWER DN. When a button is pressed from this display, the ADS1232REF

powers the converter on and returns to the analysis display, exiting configuration mode.

This mode can be used to test the current consumption of the board when the ADS1232 is powered down.

Offset calibration: When either PARM button is pressed on this screen, the ADS1232REF initiates a

hardware offset calibration on the ADS1232 by providing two extra shift clock cycles on the next data read

cycle, as described in the ADS1232 data sheet.

When either PARM button is pressed, the display briefly shows OK, indicating that calibration was

performed.

Offset calibration is performed when the ADS1232REF is powered on, but is not automatically performed

at any other time.

Version number: This screen displays the version number of the ADS1232REF firmware.

13

SBAU120B

– November 2005 – Revised July 2011

ADS1232REF User

's Guide

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