I am designing my own router on/off control to be activated from pin 15 of the breakout box. Can anyone comment on the voltage/current sink/source capabilities of the controller through this pin? Thanks!
This might help~
Ron, thanks for the reply! I’ve got the parts to build a switch in my junk box, and free beats $30.00, especially after giving my bank account a hernia buying my machine. I just need to know what the Raspberry Pi switching parameters are so that I don’t strain the little darling. It would be nice if I could drive my relay directly, but I am prepared to use a transistor driver if I have to.
~Mike
FYI - A Raspberry PI’s I/O and everything on the Buildbotics I/O is 3.3v and cannot tolerate 5v.
15ma source max. Recommend a level shifter or an optoisolator to protect the RPI.
Hi all,
My 2 cents.
We have had our machine now for a few months and I have the controller connected to the Always On plug on the IOT relay and we have not had any problems with it so far. The longest carve we did so far was about 2 hours but I don’t think running longer jobs would have any adverse effect.
Hello, is your Makita router 110v or220v, if 220V, how did you connect to break-out board ?
Hey all, hey Michael @SailorMike, hey Tom @cyberreefguru, hey
Julian @OneCNC
sorry for replying in an old thread, but there is a new user here that spreads the same question all over the older postings instead of clicking on the links in posts I provide him.
The pins of the 25-pin I/O port come directly from the AVR ATXMEGA192A3U microcontroller on the Onefinity’s mainboard, not from the internal Raspberry Pi 3B. See Schematic diagram. So the inputs and outputs of 25-pin I/O port are like described in the AVR’s microcontroller manual: 3.3 V voltage and very few milliampères max. current draw. If you look at the code, most of the pins of the AVR are programmed with the internal pullup resistor enabled.
The internal Raspberry Pi exchanges data with the AVR ATXMEGA192A3U (datasheet) only via I²C Bus (SDA/GPIO2 (pin 3) and SDC/GPIO3 (pin 5)) (which enables the Raspberry Pi to upload code to the AVR and the ATTiny on firmware updates) and over the serial interface (TXD/GPIO14 (pin 8), RXD/GPIO15 (pin 10) and CTS/GPIO16 (pin 36 of Raspberry Pi GPIO header)).
The latter is how the CNC Controller part works, by the bbserial.ko kernel module (See also Deep dive: Hacking the 8-bit AVR – By Joseph Coffland).
Note that there is also a TinyAVR microcontroller on the board which measures and controls current that is connected to the same I²2 bus than the main AVR.
The Raspberry Pi inside the Onefinity Controller, as usual, runs with 5 V.
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Hey Julian,
With this link, Jon Gordon @exineport already answered to your question above. If you don’t click on the links then you cannot be helped.
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