1. Original (not derivative)
2. Header: Project, Purpose, Author, Date, MCU, Status, Reference, Notes, etc. (edit Bareminimum.ino sketch for consistency/productivity/efficiency gains)
3. Formatted
4. Modularity: highly cohesive; loosely coupled
5. Hierarchical Design (Scalable): highly-leveraged code, threaded from global/class constants and variables, ensures a robust response to changing project task size
6. Scope: priority for local variable declarations over global
7. Well-named, consistent, identifiers for variables
8. Primitive Data Types: Judiciously chosen memory sizes as per (partial) table below, all appropriately initialized
   
   

   Arduino	AVR-libc (preferred)	Bytes	Range	Comments
   void	void	0	none
   bool, boolean	bool	1	false, true
   char	int8_t	1	[-128,127]	ASCII Character or Signed (2's complement) 8-bit integer
   byte	uint8_t	1	[0,255]
   int, short	int16_t	2	[-32768,32767]
   unsigned int	uint16_t	2	[0..65535]
   long	int32_t	4	[~2^31-1, 2^31]
   unsigned long	uint32_t	4	[0,2^32-1]
   float	float	4	[~-3.4×1038,~3.4×1038]
   double	double	4	Same as float on the Arduino platform

9. Composite Data Types used for high cohesion (arrays, structs, etc.), all appropriately initialized
10. Efficient
11. Application Specific Complexity (whichever is appropriate for the context): eg. high-level vs register-level or polling vs interrupts
12. Well-documented throughout
13. Easy to read (no attempt to be cryptic aka, show off)
14. Keep statements lengths to the width of your IDE
15. Any others ?

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