122-28176 Parallax Inc, 122-28176 Datasheet - Page 161

• 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

Part A:
Currently in PwmCommand.bs2’s
repetitions for a PWM time of 100 ms. This allows 1.5 seconds for the fan to reach a
new speed prior to taking a reading.
How does your plot change?
Part B:
Another issue in controlling and monitoring the fan's speed is the fact that drive is only
applied while the PWM command is being executed. With this very short program, not
much occurs outside of applying and measuring the drive. What if there was other
control and monitoring action that had to occur? How would that affect the fan's speed?
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1. What happens to the fan's speed with the simulated delay time of 2 seconds?
2. If the delay in execution was required, but proper sampling of RPM after driving
Save PWMTest.bs2 under a new name.
Modify the
a measurement.
Modify the bolded lines of the PwmCommand.bs2’s Main Routine:
was needed, where would be a better place for the simulated code delay? Test
your idea.
DO
LOOP
Duty = 75
DEBUG "!TEXT (PTIME),98A,0.8A,(BLACK),",DEC Duty,CR
GOSUB Apply_Drive
PAUSE 2000
COUNT Opto_SW,100,opto_count
Per_RPM = Opto_Count * 100 / Max_Count
DEBUG DEC Duty, ",", DEC Per_RPM ,CR
Apply_Drive
subroutine to apply PWM for 5 seconds prior to taking
Apply_Drive
subroutine, the PWM is applied for 15
'Simulated code delay time