Ok, tanks for the link. It’s a train so you only need forward and back and how fast. So what exactly is happening to your PI Zero’s? What part gets “killed”?
I am also using the camera, how would i know what is wrong with it! they just don’t run. completely dead
I have manage to get it to work a little bit but after running it backwards a forwards a few time it seems to freeze some time I am able to reboot & do i it again then the next thing i know i have a dead pi
I have been running another one for the last 2 or 3 day with nothing attached other than the camera I noticed to day that it also appears to have hung but it has now rebooted ok (why would this be?)
It would seem disingenuous, since the motor drivers are supposed to protect against these kind of things, but I wonder if it’s back-emf from the motor? I learned the hard way that the voltage induced by collapsing magnetic fields can be severe- IE: I blew up a Flotilla dock plugging a cheap microUSB fan into it. Turns out it was shooting ~60v pulses back into the port!
Yes i think so two. so how do i connect with a 9volt battery and very little space i dont mind buying something that will work just dont know what!
Anyone know how to resolve this?
Is that motor driver board 3V logic safe? What I mean is no pull ups to 5V etc. It’s passive right, it only receives a signal in, nothing coming out going into the Pi?
How would i know? Sorry my electric skills very limited
It’s usually in the product description etc. I buy a lot of small breakout boards with sensors on them. Like this one for example, https://www.adafruit.com/product/1777 In the description it says, "We wrapped this nice little sensor up on a PCB with level shifting and regulation circuitry so you can safely use it with 3 or 5V ".
Arduino uses 5V logic and the Pi uses 3V logic. That board has a 5V in and a 3.3V in. On the Pi you use the 3.3V in pin. That board uses i2c for communication, if I were to wire it up to 5V it would damage the Pi.
If I see something I want, advertised for Arduino, I read the fine print to make sure its usable with a Pi.
@gadgetoid likely has a better handle on this than me. I 'think" PWN is one way, from the Pi to the motor driver, so there shouldn’t be any signal coming back to the Pi to damage it. Unless there is a pull up to 5V on the motor driver board? What you could do, if you have a volt meter, is power up the motor drive board with the Pi disconnected and see if there is any voltage on the PWN pins etc.
Would putting a diode between the pi and drive board help?
According to this, https://www.bananarobotics.com/shop/How-to-use-the-HG7881-(L9110)-Dual-Channel-Motor-Driver-Module
“These chips have built-in output clamp diodes to protect your sensitive microcontroller electronics.”
The question is what do they clamp too? The description takes about Arduino so my guess is 5V.
Looking at the pictures I can see 4 resistors right by the inputs I suspect are pull ups. Without a schematic its just a supposition on my part. Putting a series diode in the circuit may break the logic in places where a high does one thing and low does another.
Normally with say a relay, a back EMF diode would be used to supress spikes. You can’t do that with a motor that reverses polarity to reverse direction though.
If its killing your Pi’s something isn’t right? You may need a logic level shifter between your Pi and the motor driver. Something like this https://www.adafruit.com/product/1875
I will have a look at that when I get a chance. Just switched ISP’s and I’m playing catchup with changing my e-mail on every forum etc.
Looks Ok to me. post must be 20 characters so adding test, lol. .