I am working on a project to control the temp of a device using a DS18B20 1wire sensor and a pump. The response of the cooling process is fairly quick and the Dallas 1 wire sensors take about 750 ms to read. I have tried to change the resolution but the tests still come back at 729 to 750 ms. Is there anyway to improve the response time? Either I am missing something or it is hard coded in the kernel. I considered other options like:
- using the PRU to read the sensors but it looks very complex.
- adding an arduino to read the sensors at a lower resolution but I then get the complexity of communication.
- Using a thermistor and the ADC but I would have to re wire part of the unit I am controlling.
Any advice would be greatly appreciated.
Greg
BBB and DS18B20 performance
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- adafruit_support_mike
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Re: BBB and DS18B20 performance
I doubt there's anything in the kernel, but any intermediate code you're using might have a fixed delay built in.
If you're willing to run another wire, the MCP9808 is an I2C temperature sensor that's accurate to 0.5C at 33sps:
https://www.adafruit.com/products/1782
That's about the fastest temp sensor we have.
If you're willing to run another wire, the MCP9808 is an I2C temperature sensor that's accurate to 0.5C at 33sps:
https://www.adafruit.com/products/1782
That's about the fastest temp sensor we have.
-
- Posts: 16
- Joined: Tue Feb 21, 2012 12:35 pm
Re: BBB and DS18B20 performance
Thanks, I think I am going go with the thermistor. Setting up the ADC is easy though I may need to do some calibration in the code. Fast, cheap, simple and relatively accurate.
I may give the PRU another go first though.
Greg
I may give the PRU another go first though.
Greg
Please be positive and constructive with your questions and comments.