Reduce some var usage, add arg checks, adjust error codes
Adjust error codes
Add SCPI include for error codes
Reduced load I coefs from 4 x array to single structure as all members
equal
Added second ptr arg check
Adjusted error codes, added arg checks
changed error values, added arg checks
corrected function return
Corrected function return type
Updated error values, added arg checks
Updated error values
Updated error codes
Removed pwm 2 & 3 prd consts as equal to 1 prd
Updated PWM 1 const usage
Updated error numbers, added arg checks
Updated error numbers
Corrected updated error number constant names
Reordered function defs to allow removal of mass static function decls.
Corrected static function decl order
Updated error numbers, removed unused set/get for sine state