SPUSI2/NOPB National Semiconductor, SPUSI2/NOPB Datasheet - Page 12

• Manufacturer Part Number: SPUSI2/NOPB
• Description: BOARD EVAL DATA CAPTURE BOARD
• Manufacturer: National Semiconductor

Specifications of SPUSI2/NOPB

• Main Purpose: Interface, Data Capture
• Embedded: Yes, MCU, 8-Bit
• Utilized Ic / Part: WEBENCH® Sensor Designer Boards
• Primary Attributes: USB Interface Dongle II
• Secondary Attributes: SPI Interface
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: SPUSI2

4.2.3.1 Calibrating End Points.
in the calibrate window. Then enter the expected sensor value, such as degrees
or inches, from an independent reference measurement.
corresponding button to “Capture Reference Point.”
immediately unless both have the same ADC code which is invalid. An OK
button appears when a valid calibration data pair has been entered.
4.2.3.2 Calibration Computations.
To calibrate the sensor to reference end points, first select the proper units
Repeat the process for a second data point.
Note that the two data points must read different ADC codes.
Data points can be reentered and simply replace the previous entry.
The slope and intercept values from the entered data are displayed
The user may select Revert or Cancel to keep to the original values.
The calibration computations are used for linear extrapolation.
From the user data –
This allows any code value to be mapped to sensor values:
Slope
Intercept
m
= (RefVal2 – RefVal1)/(Code2 – Code1)
Figure 4-9: Window after second capture.
b
Figure 4-8: Window after first capture.
= RefVal1 –
m
* Code1
Then click on the