Hi guys,
I'm new to the site, but figured I'd quick introduce myself and ask my question. I'm Evan, 27 y/o, and have an BSEE from San Diego State in 2007. I've specialized in motorcycle charging systems & electronics (designing & manufacturing stators, flywheels, voltage regulators, etc = more electromagnetics and mechanical design than EE work) for the last couple years.
I did take some embedded computing courses as electives in college, but overall I'm pretty new to microcontrollers.
I have available to me a Microchip PIC, programmer, and dev board, and a Parallax Basic Stamp and dev board, so I can use either to do this project.
Once get this working I can port my code to use either platform.
Now on to my problem!
I don't want to describe the overall purpose of this project, as I'm hoping to finish a product to bring to market eventually.
The issue I'm having is measuring a low resistance (0Ω-150Ω) with a microcontroller. I have tried to do this using the RCTIME function with the Basic Stamp, but this function is based on measuring the time to discharge a capacitor through the unknown resistance, and is not accurate at such low resistances. Adding a ~1k resistor in series brings it into the RCTIME functions useful range, but makes the low changes in resistance negligible.
I'm basically measuring the resistance of a potentiometer and upon knowing the value, manipulate output pins on the uC based on the resistance.
Any ideas on how to make this measurement in this low resistance range?
I'm new to the site, but figured I'd quick introduce myself and ask my question. I'm Evan, 27 y/o, and have an BSEE from San Diego State in 2007. I've specialized in motorcycle charging systems & electronics (designing & manufacturing stators, flywheels, voltage regulators, etc = more electromagnetics and mechanical design than EE work) for the last couple years.
I did take some embedded computing courses as electives in college, but overall I'm pretty new to microcontrollers.
I have available to me a Microchip PIC, programmer, and dev board, and a Parallax Basic Stamp and dev board, so I can use either to do this project.
Once get this working I can port my code to use either platform.
Now on to my problem!
I don't want to describe the overall purpose of this project, as I'm hoping to finish a product to bring to market eventually.
The issue I'm having is measuring a low resistance (0Ω-150Ω) with a microcontroller. I have tried to do this using the RCTIME function with the Basic Stamp, but this function is based on measuring the time to discharge a capacitor through the unknown resistance, and is not accurate at such low resistances. Adding a ~1k resistor in series brings it into the RCTIME functions useful range, but makes the low changes in resistance negligible.
I'm basically measuring the resistance of a potentiometer and upon knowing the value, manipulate output pins on the uC based on the resistance.
Any ideas on how to make this measurement in this low resistance range?