Parameters In Analysis Mode - Texas Instruments ADS1230REF User Manual

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3.4 Configuration
To enter Configuration mode, press the VALUE buttons simultaneously. The four buttons then assume the
functions shown in the CONFIG box. To exit Configuration mode, press the VALUE 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 PARM buttons. To change the parameter values, use the VALUE 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
SEL or ENT.
Although a few of the parameters in the Analysis and Scale configuration menus are the same, the
settings are kept separate between the modes.
Table 5 summarizes the available parameters.
Parameter
Averages
Voltage Reference
Power-down mode
Offset calibration
Save parameters
Version number
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, and 128. The default setting is 50.
Voltage reference: To convert voltages to codes, the ADS1230REF 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 PARM buttons to select a
digit, and the VALUE 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 ENT or SEL is pressed on this screen, the ADS1230REF causes the
ADS1230 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 ADS1230REF
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 ADS1230 is powered down.
Offset calibration: When ENT or SEL is pressed on this screen, the ADS1230REF initiates a hardware
offset calibration on the ADS1230 by providing two extra shift clock cycles on the next data read cycle, as
described in the ADS1230 data
When ENT or SEL is pressed, the display briefly shows OK, indicating that calibration was performed.
Offset calibration is performed when the ADS1230REF is powered on, but is not automatically performed
at any other time.
Version number: This screen displays the version number of the ADS1230REF firmware.
SBAU125A – August 2007 – Revised September 2007
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Table 5. Parameters in Analysis Mode
Display
AVG=
VREF=
PDWN?
OCAL?
SAVE?
V1.0.0
sheet.
Value Range
2–128 Number of points for average,
peak-to-peak, and RMS modes
0.5–5.0 Voltage used in various
calculations
— Power-down mode; see
— Offset calibration; see
— Save parameters; see
— Firmware version number display
ADS1230REF User's Guide
Analysis Mode
Description
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