[Grbl_Esp32 Issue#247] Provide for conditional include of user spindle curve

Please describe the feature you would like implemented

Provide for conditional inclusion of user source file spindle_curve.h to recalculate rpm to linearise response.

Why do you think this would improve Grbl_ESP32?
Allows user mod without touching a managed source module

Will this feature appear to a lot of users?
Probably.

“text
diff --git a/GrblEsp32/spindlecontrol.cpp b/GrblEsp32/spindlecontrol.cpp
index 1886983..4b36600 100644
--- a/GrblEsp32/spindlecontrol.cpp
+++ b/GrblEsp32/spindlecontrol.cpp
@@ -111,6 +111,11 @@ uint32t spindlecomputepwmvalue(float rpm)
// Compute intermediate PWM value with linear spindle speed model.
// NOTE: A nonlinear model could be installed here, if required, but keep it VERY light-weight.
sys.spindle_speed = rpm;
+#if defined _hasinclude
+ #if _hasinclude("spindle_curve.h")
+ #include "spindle_curve.h"
+ #endif
+#endif
pwmvalue = floor((rpm-settings.rpmmin)*pwmgradient) + SPINDLEPWMMINVALUE;
}
return(pwm_value);
@@ -169,4 +174,3 @@ void spindlesetenable(bool enable)
#endif
#endif
}
-
`

Sample user spindle_curve.h (not to be included in managed source).

`text
//optional user customisation of spindle PWM curve
//needs consistent settings.rpmmin and settings.rpmmax
//use block to make vars private
{
// static long spdcuri[]={0,24000,1000000};
// static float spdcurm[]={0,1,0};
// static long spdcurb[]={0,0,24000};
static long spdcuri[]={1000,3360,5760,24000,1000000};
static float spdcurm[]={0,0.1412,0.325,0.8872,0};
static float spdcurb[]={0,1013,382,-2592,24000};
int i;
for(i=0;i``

Tested and working.

Owen