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bogde / HX711

An Arduino library to interface the Avia Semiconductor HX711 24-Bit Analog-to-Digital Converter (ADC) for Weight Scales.
MIT License
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Response time issue & readings spontaneously terminating #203

Open creechr opened 3 years ago

creechr commented 3 years ago

I'm building a set of pedals for my sim racing rig and I'm using 3 load cells paired with HX711 boards connected to a teensy 4.1. I'm using some code I found that configures the teensy to be read as a USB joystick device. I've gotten everything working although I still have the two following issues and would greatly appreciate some help solving them.

  1. The response time for the pedals is too slow. There's probably like a 1/4 second lag from pressing the pedal to the corresponding joystick reading. I'm not really sure where the issue is coming from. It's probably either being slowed down somehow in transit through the USB joystick library or slowed by the HX711 board itself.

  2. The HX711 boards seem to go into some sort of sleep mode at random. There is no discernible pattern they'll just suddenly stop sending readings to the teensy. The voltage on the DT pin goes from 3.3 to ~0.6 and then no reading goes through. This usually happens after a few minutes after powering up to one of them and then gradually to the others until they all stop working.

Any help would be greatly appreciated. Below I've linked a zip file with all my code. I used Visual Studio Code with the Platform.IO extension to write it.

Thanks, Chris

SimRacingPedals.zip

aspdigital commented 3 years ago

"The HX711 boards seem to go into some sort of sleep mode at random." Actually, they don't -- read the data sheet. On page 5:

"When PD_SCK pin changes from low to high and stays at high for longer than 60us, HX711 enters power down mode (Fig.3). When internal regulator is used for HX711 and the external transducer, both HX711 and the transducer will be powered down. When PD_SCK returns to low, chip will return back to the setup conditions before power down and enter normal operation mode."

Make sure that the process of reading out the chip isn't interrupted.