> For the complete documentation index, see [llms.txt](https://irnas.gitbook.io/opencollar/-MDJCI9OmpOqWrQzjNIR/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://irnas.gitbook.io/opencollar/-MDJCI9OmpOqWrQzjNIR/firmware/settings-module/settings-json.md).

# Settings JSON

Settings, values, commands and messaging structures.

## settings.json

Settings, values, commands and messages are determined by the settings.json structure, that is parsed in build time to several .h and .c files, as described below. 

It contains the following main fields:

* **fw\_version**
  * **major**
  * **minor**
* **hardware**
  * **type** - firmware type, for example "wisentedge\_nrf52840"
  * **version**
    * major
    * minor
* **settings**
  * **port** - port on which settings are sent and received from
  * **type** - settings type, based on tracker type
  * **setting of the form:**
  * setting\_name
    * id - for "basic settings" from 0x01 to 0x0F, for "advanced" from 0x11 to 0x9F
    * enabled - true or false 
    * default - default value
    * min - min value
    * max - max value
    * length - in bytes
    * conversion - data type, possible options:
      * uint8, uint16, uint32, int8, int16, int32
      * float
      * byte\_array
      * bool
* **commands**
  * **port** - port on which commands are sent and received from
  * **commands of the form:**
  * command\_name
    * id - from 0xA1 to 0xCF
    * length - length of send command value, if 0 none
    * conversion - data type of send value, if there is non uint8 is used
    * value - default value, 0 if none
* **values**
  * **port** - port on which settings are sent and received from
  * **values of the form:**
  * value\_name
    * id - from 0xD1 to 0xEF
    * enabled - true or false 
    * default - default value
    * min - min value
    * max - max value
    * length - in bytes
    * conversion - data type, possible options:
      * uint8, uint16, uint32, int8, int16, int32
      * float
      * byte\_array
      * bool
* **messages**
  * **messages of the form:**
  * message\_name
    * port - to send message on
    * id - from 0xF1 to 0xFF
    * length - in bytes
    * conversion - data type, possible options:
      * uint8, uint16, uint32, int8, int16, int32
      * float
      * byte\_array
      * bool

## Python parser

Python parser `py2h.py` and validation script `validate_data.py` are used to convert `settings.json` file to c files. 

In particular the following files are generated:

* `hardware_def.h` - containing only definitions from "hardware" field
* `settings_def.h` and `settings_def.c` - containing settings structure and auto-generated functions for access and writing to structure
* `commands_def.h` and `commands_def.c` - commands defines and settings
* `values_def.h` and `values_def.c` - containing main values structure and auto-generated functions for access and writing to structure
* `messages_def.h` and `messages_def.c` - message defines and messages

All auto-generated files are equipped with `/* AUTOGENERATED FILE - DO NOT MODIFY!  */` comment. Sections below describe content of each generated file and helping files.