A grblHAL driver for the Texas Instruments Tiva C (EK-TM4C123GXL) Launchpad
See the Wiki-page for compiling grblHAL for instructions for how to import the project, configure the driver and compile.
Available driver options can be found here.
Optional support for I2C keypad added, can be used for jogging and mist/coolant overrides. Jogging can be toggled between fast, slow and step mode. Laser PPI mode (PPI - Pulses Per Inch) may also be enabled, this to ensure constant power delivered to the workpiece regardless of speed. PPI mode parameters are set by some user-defined M-codes:
<n> = pulses per inch.
<n> = pulse length in microseconds
Default pin assignments matches the CNC BoosterPack
NOTE: R9 and R10 should be removed from the LaunchPad and the appropriate shorts (0R resistors) added to the CNC BoosterPack when this is used with the default pin assignments. Also, Q1-Q3 should possibly be removed as they act as pull-downs for limit switches inputs, not the best if these inputs are to be configured with weak pull-ups.
NOTE: Only tested on my bench with an oscilloscope. A slightly different driver has been used for my CO2 laser cutter/engraver for a while, this on a custom PCB.
2021-08-11