122-28176 Parallax Inc, 122-28176 Datasheet - Page 196

• Manufacturer Part Number: 122-28176
• Description: GUIDE STUDENT PROCESS CONTROL
• Manufacturer: Parallax Inc

Specifications of 122-28176

• Accessory Type: Manual
• Product: Microcontroller Accessories
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• For Use With/related Products: Propeller Education (PE) Kit
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Contains lead / RoHS non-compliant

ACTIVITY #2: SIGNAL CONDITIONING
The analog to digital converter resolves an analog value to a digital value.
ADC0831, as configured, coverts an input voltage of 0 to 5 volts to an 8-bit value (byte)
of 0 to 255, respectively, as shown in Figure 6-4. The reason for the value of 255 is that
the ADC0831 is an 8-bit ADC. The maximum value of 8 bits is 255. When looking at a
binary value, such as 11111111, each position from right to left is a higher power of 2,
with the Least Significant Bit (LSB – right most) having a value of 2
Significant Bit (MSB – left most) has a value of 2
would be the sum of each position with a 1 or:
A binary value of 10011001 converted to decimal would be:
Figure 6-4 shows that the input voltage (0-5 V) is resolved to a binary value (0-255).
This linear transfer function can be written as a line equation:
128 + 64 + 32 + 16 + 8 +4 + 2 + 1 = 255
128 + 0 + 0 + 16 + 8 + 0 + 0 + 1 = 153
y = mx + b
7
or 128. A binary value of 11111111
Figure 6-4
Voltage to Binary
Conversion Transfer
Function
0
, or 1. The Most
The