OpenBuilds Documentation

OpenBuilds BLOX provides support for using an RC servo to raise/lower a pen, in Pen Plotter type applications, or other imaginative uses

Make sure to set $33=50 in grblHAL settings (CONTROL > Grbl Settings Tab > Scroll down to $33 Spindle PWM Frequency > Set the value to '50' and Save

TIP: Set $33=50 (PWM frequency), $34=5, $35=5 and $36=10 to generate a “standard” PWM signal: 20ms repetition rate, 1 - 2ms pulse length range. You may decrease $34 and $35 to output a shorter pulse than 1ms at min, and increase $36 to get a longer pulse than 2ms at max.

For most standard RC Servos that have moves 180 degrees when $34 and $35 are set to 2 and $36 to 15 - resulting in a 0.4 - 3ms pulse witdh range.