C File Templates

Welcome to the C File Templates repository! Here you will find templates for both .c and .h files that you can use as a starting point for your embedded C projects. The templates are designed to provide standard structure and a naming conventions, helping you to write clean and organized code.

Type of Files

File	Description
PREFIX_ModuleName.c	Implementation file for ModuleName. Never add typedef or #define macros in this file. Use the PREFIX_ModuleName_Priv.h for that instead.
PREFIX_ModuleName.h	Public interface. It includes all the ModuleName public declarations.
PREFIX_ModuleName_Priv.h	Private header. It includes all the ModuleName private declarations (e.g. configuration macros).

Naming Conventions & Coding Style

Prefixes

• The prefix for the module should consist of 2 to 4 capitalized letters that indicate its place within the software architecture.

• Here are some examples that you can use:

  Prefix	Description	Example
  APP	Application layer	APP_SystemManager.c
  SYS	System and MCU setup	SYS_Includes.h
  BSP	Board Service Package	BSP_UserButton.c
  DRV	Driver	DRV_GPIO.c
  OS	Operating System	OS_FreeRTOS.c
  HAL	Hardware Abstraction Layer	HAL_STM32L4xx.h

Functions

• Function names should include a prefix as well.

• This should be an uppercase abbreviated version of the module it belongs (2-4 characters).

• Notice that this prefix is different from the ones use to name the module files.

  Example:

  /** A function inside the DRV_ADC.c module */
  void ADC_StartConversion(void);

Macros

• Macros names should also include a prefix with its module name (2-4 characters) and be declared in uppercase.

  #define ADC_CHANNELS_NUMBER  19

• Avoid using an _ as prefix for macros since these are usually system-defined or reserved.

• The only exception to this rule is the inclusion guard macros (used to avoid recursive inclusion of header files).

  #ifndef ___PREFIX_MODULE_NAME_H
  #define ___PREFIX_MODULE_NAME_H
  
  /* some code */
  
  #endif

Type definitions

• Typedef names should also include the module name prefix and the _t suffix.

• This applies for both enum and struct.

  typedef struct
  {
     /* some code */
  } DRV_ADC_ChannelConfig_t;

Variables

• Start variable names always with a letter and use camelcase to separate different words.
• Avoid using _ to separate words at least if it's a suffix like an engineering unit (e.g. _mV).
• Begin the name of local variables (intended as global just within a single file) with the letter l.

uint16_t lBatteryVoltage_uV = 0;

• Begin the name of pointer variables with p.
• Begin the same of local pointer variables with lp.

DRV_ADC_ChannelConfig_t * lpMotorAdcConfig = NULL;

Comments

• Only use the /** */ sequence for comment blocks. This will be later used by Doxygen for self-documentation.

• Use /* */ for "on-line" comments. Avoid breaking an "on-line" comment into multiple lines.

  /* AVOID THIS */
  uint8_t lMotorCurrent_mA = 0; /* This variable stores the last ADC
  value of the motor current in mA. */
  
  /* DO THIS*/
  /* This variable stores the last ADC value of the motor current in mA. */
  uint8_t lMotorCurrent_mA = 0;

Line width

• Don't write lines of code longer than 120 characters.
• If you're using VS Code you can set this up with "editor.wordWrapColumn": 120 in settings.json.