Blew up my Toolboard - PB8 for 4028 PWM?
I followed the instructions to disable 100% fan at startup, attaching the 4028 black wire to HE3- (red wire to FAN6+ set to 12V), and the PWM wire to PA0 on the toolboard. The
I had updated printer.cfg with the correct pin beforehand (with a save&restart), but attached the PWM pin to PB8 while everything was on. Either way, the fan was set to 0% when I pushed the pin in PB8 so I wouldn't expect the fan to turn on at all.
This is from my printer.cfg (copied and modified from RatOS.cfg): I have similar for t0 but I hadn't hooked anything up to that yet.
enable_pin with HE3 seemed to work, but the fan was running 100% regardless of level I selected in the UI, besides 0% which turned it off.
Thinking maybe something wrong with toolboard_t1:PA0, I tried attaching the PWM wire to toolboard_t1:PB8 (the bottom pin of the probe port). As soon as I did this, the fan turned on unexpectedly for a moment, then everything crashed claiming comms lost with toolboard_t1. It looks like it's fried, no status lights on the toolboardl, RPi hat status light for that port is dark.
Was there something special about that pin? What did I do wrong?I had updated printer.cfg with the correct pin beforehand (with a save&restart), but attached the PWM pin to PB8 while everything was on. Either way, the fan was set to 0% when I pushed the pin in PB8 so I wouldn't expect the fan to turn on at all.
This is from my printer.cfg (copied and modified from RatOS.cfg): I have similar for t0 but I hadn't hooked anything up to that yet.
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Okay so this was a replacement fan from Amazon and I think the blue wire on this one is the tach wire, not the PWM wire. I didn't even consider that wire colors would be different.
So if I hooked up the tach wire to the PWM pin, would that have this effect? I did see something about how you can blow something if you do this configuration with the tach pin connected
Is there a good way to confirm the wires? I assume it's easy with a scope to identify the tach, but I don't have a scope
Update: I got a new tool board and carefully tested everything and can definitively confirm it was a wire color switch.
RatRig 4028 fan : - Blue: PWM - White: Tachometer The Amazon 4028 fan (https://a.co/d/8OmM3yR): - Blue: Tachometer - Yellow: PWM So on this Amazon fan, the yellow wire is the PWM wire which needs to be attached to
The warning on the RatOS docs about blowing up your MCU if you use the tach wire while also using the HE1- port hack (to disable 100% fan at startup) is exactly what happened to me. Luckily it was just the tool board, not the whole MCU, but still cost $30 to replace it.
RatRig 4028 fan : - Blue: PWM - White: Tachometer The Amazon 4028 fan (https://a.co/d/8OmM3yR): - Blue: Tachometer - Yellow: PWM So on this Amazon fan, the yellow wire is the PWM wire which needs to be attached to
toolboard_t[0|1]:PA0.The warning on the RatOS docs about blowing up your MCU if you use the tach wire while also using the HE1- port hack (to disable 100% fan at startup) is exactly what happened to me. Luckily it was just the tool board, not the whole MCU, but still cost $30 to replace it.
nicely tracked down