tinyG headers. Enable active low?

Started by kiwigrant on Jan 19, 2017 in TinyG Support. 2 replies, last activity Jan 21, 2017.

kiwigrant Jan 19, 2017 #

Im curious to know why the TinyG didn't come with Step and direction headers.. Seems like a bit of an inconvenience to add them.

In thinking about it, because I only step and direction I m wondering why I even went with Tiny8 (V8) - could I have gotten away with and Aduino and loaded the GRBL s/w or the G2 software into a Due and just and picked up step, direction and enable from there.

As it is Im have to add Voltage shifters on the Step DIR o/p and need to invert the "enable" output.

I also find it peculiar that the enable is active "low" this doesnt seem to fail safe. i.e. a wire break stops the motors.

Don't get me wrong - Not complaining just a bit more work then I had anticipated.

cmcgrath5035Staff Jan 20, 2017 #

TinyG has been around for a while, and was 4-on-board-drivers centric.
Folks pushing the envelope added external drivers to the mix, and accommodating pins were added.
GRBL is only 3 motor processing(I believe), but you are correct that G2/DUE are worth considering for users targeting external drivers (up to 6 motors).
If your chosen external drivers are 5V logic you will have to buffer and level translate DUE as well.

Enable active low is likely a side effect of using TI drivers.

kiwigrant Jan 21, 2017 #

Thank you for the response. Im up and running now.

These learning are part of the fun, and the reason why i started down this road.