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Published 20 hours ago • verified publisher icon synthetos

Feature Request: pad for measuring voltage at pin 8 (VREF)

Open liqdfire opened this issue 9 years ago • 0 comments

The TI documentation states that the current being driven to the motors can be calculated by measuring using the following formula I = Vvref / (8 * RISENSE)

For the gShield RISENSE is 0.1 ohm, so the formula can be reduced to I = Vvref / 0.8

Currently the method of calculating current pushed to the motors as described on this page [https://github.com/synthetos/grblShield/wiki/Using-grblShield#setting-motor-current] involves turning the current pot up until thermal shutdown is reached.

It would be a lot easier and more accurate to just have the VREF pin drawn out to a small pad that can be used to calculate the current.

liqdfire avatar Jan 13 '16 02:01 liqdfire