Spin Code for eTape Liquid Level Sensor (Parallax Item: 29131)

SEL

Has anyone used this object with the Propeller. If so will you direct me to an Object or example code.

Thanks

SRLM

The eTape sensor appears as a resistor in electrical circuits, so any method of measuring resistance using an analog to digital converter (ADC or A/D) would work.

Peter Jakacki

I would have thought the RC timing object would be the ideal candidate for this.

Bob Lawrence (VE1RLL)

The Bs2 example used RC timing(as Peter mentioned)

File...... eTape Simple.bs2
' Purpose... Simple program using RCTIME to get the results from the eTape Sensor
' Author.... Technical Support -- Parallax, Inc.
' E-mail.... support@parallax.com
' Started... 9/23/09
' Updated... N/A
'
' {$STAMP BS2}
' {$PBASIC 2.5}
'
' =========================================================================


'

---

[ Program Description ]

---

' This is a small program used to pull the values from the eTape sensor using
' RCTIME. This demo will display the results to the DEBUG terminal. The cap
' used in the demo is a 0.1mF.


http://www.parallax.com/StoreSearchResults/tabid/768/List/0/SortField/4/ProductID/590/Default.aspx?txtSearch=eTape+Liquid+Level+Sensor


http://www.parallax.com/Portals/0/Downloads/docs/prod/sens/eTape_ExampleCode.zip

Peter Jakacki

Since the resistance of the sensor ranges from 600ohms down to 80 I would use a larger value capacitor to increase the resolution. However, capacitors tend to vary in capacitance with temperature and aging so I would at least use an extra I/O with a 1% fixed resistor that can be used with the same capacitor to calibrate and compensate the circuit. Circuit configurations can vary to suit the application and software may measure the charge or discharge of an RC circuit. RCTIME is a very easy thing to implement in any code, SPIN and PASM included.

SEL

Thanks to ALL!

You have put me on the right trail.

Stan