Teensy 4.1 stalls?

G

gndTeensyBoard

Member
Hello! I would like some guidance on an issue I am having thus far with the Teensy 4.1 board. It tends to randomly stall every now and then. The project I am working on has a blower engine within half a foot from the Teensy board and it only stalls when I crank that engine on. Sometimes it may happen within seconds, other times it may happen many minutes later. When it stalls the Teensy boards orange led dies but all the GPIO stay stuck to whatever output or input they are at. Also at that point the USB port is not found anymore on my Arduino IDE.

A bit of a background of this project is that I am using the engine with a motor to produce AC power that feeds into a rectifier that produces DC power. The Teensy board controls certain relays, collects and calculates power, runs a display, and controls the throttle of the engine. I would like to show you the schematic but unfortunately it's restricted under my projects documents. Any suggestions are welcomed.
 
You'll need to protect the teensy and its wiring from the EMI produced by the blower motor. Is the teensy in a grounded metal box? That's the bare minimum you need to do.
 
BriComp said:
Difficult to say without seeing the code!
Click to expand...
While it could be some bug that is causing the code to lock up given the environment it's more likely to be a electrical issue than firmware. Sounds like the setup is going to be inducing all sorts of voltage spikes onto any unshielded wires and circuits.
 
gndTeensyBoard said:
Hello! I would like some guidance on an issue I am having thus far with the Teensy 4.1 board. It tends to randomly stall every now and then. The project I am working on has a blower engine within half a foot from the Teensy board and it only stalls when I crank that engine on. Sometimes it may happen within seconds, other times it may happen many minutes later. When it stalls the Teensy boards orange led dies but all the GPIO stay stuck to whatever output or input they are at. Also at that point the USB port is not found anymore on my Arduino IDE.

A bit of a background of this project is that I am using the engine with a motor to produce AC power that feeds into a rectifier that produces DC power. The Teensy board controls certain relays, collects and calculates power, runs a display, and controls the throttle of the engine. I would like to show you the schematic but unfortunately it's restricted under my projects documents. Any suggestions are welcomed.
Click to expand...
A long shot but it may be caused by electromagnetic interference from the engine. Try shielding the teensy from the motor by surrounding it with tin foil with as few air gaps as possible (i.e. a faraday cage). Ideally connect the foil to ground as well, but in one place only.
 
That is what I am observing. The controller doesn't lock up when I am just powering it with the usb power or with an external power supply. But the moment the engine of the system is cranked up and running, the controller becomes unstable and I can see this through the display that is connected to the controller. The display will flicker like a broken TV screen and eventually stop with messed up pixels. Then I will check the controller and it has froze. The little orange light on it is also no longer on.
 
You are describing the typical symptoms of putting sensitive electronics next to an RF noise generator. You need more shielding, better grounding and filtering on any cables coming in or out of the processors shielded environment.
 
In my system I am using SPI communication on a couple of devices like temperature sensors and power sensors. If any of these lines take in noise that could potential raise the voltage of the signal, would that cause the Teensy to freeze? I would assume this would only damage the pin but not cause the Teensy to freeze.
 
If the reset pin, crystal pins or the power supply(s) is affected by noise, or any pin is triggered to cause CMOS latchup, those all might well cause a freeze
 
Those instructions are a bit out of date, for a T3.2 not T4.1 which has 2 pads (yes one is VIN, the other VUSB)

Why not just cut betwen the pads, so VIN anf VUSB are no longer connected? And it's quite easy to reverse if need be, with a solder blob.

Fitting diodes to the pads would not be easy, you need top soldering skills and a very steady hand. Even then the pads may be damaged or even start peeling off the board due to the heat.
 
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Ignition systems for gas engines are the best EMI generators. Both RF and conducted.
AndyA's advice is spot on. Put anything away of the spark plug cable. Filter the power supply and I/O's with transil diodes, ceramic capacitors, and so on.
 
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