NewMCU

Introduction

This page will explain how to add a new microcontroller to the bootloader

Client

The following additions must be made on the client side

JSON

All json files which contain infromation about a microcontroller must be saved under "config/Devices". The name of the json file will be the identifier for the newly added mcu. It should be unique across all microcontrollers. You can use subfolders to organize your json files, but these will be ignored for identification of a microcontroller.

Structure

The following table will use a hierarchy format to identify json values. The following example will explain the structure:

{
  "device": {
    "general": {
      "id":   "atmega328p",
      "vendor": "Microchip",
      "arch": "AVR",
      "subarch": "ATMega",
      "name": "Atmega328p"
    }
  }
}

The arch value will be identified by the string "/device/general/arch"

Value	Description	Example Value
/device/general/id	A unique identifier for the microcontroller. It is recommended to use the same value as the filename	atmega328p
/device/general/vendor	Device Vendor of the Microcontroller	Microchip
/device/general/arch	The Architecture of the Microcontroller	AVR
/device/general/subarch	The Sub Category of the Microcontroller, can be empty if non-existent	ATmega
/device/general/name	The full Name of the microcontroller in "human readable form"	Atmega328p
/device/flash/total	Total flash space of the device	1KB
/device/flash/available	Available flash of the device. This value must be the flash size which the bootloader can access and write to.	2GB
/device/eeprom/total	Total EEPROM size of the Microcontroller (can be 0 if there is none)	0B
/device/eeprom/available	Available EEPROM size of the Microcontroller (can be 0 if there is none)	42KB
/serial/general/mode	Serial mode. (see Serial conventional notation )	8N1
/serial/general/bytesPerBurst	Bytes sent within one burst of data. This value must also be configured on the microcontroller bootloader. Setting this value too low will cause slow transfers and can cause (implementation dependent) a smaller addressable flash size. Setting this value too high will cause wasted flash space.	2
/serial/general/metadataByteSize	This is the size of bytes which metadata will use for a transmission. This metadata will be used for different values and therefore there should be enough space to fit a full flash flash size width (e.g. 128kB Flash don't fit in a 2 Byte type and need 3 Bytes or more)	2
/serial/general/minBaudrate	Minimum allowed baud rate for communication. If the implementation doesn't need this set to 0	9600
/serial/maxBaudrate	Maximum allowed baud rate for communication	115200
/serial/write/waitTimeForReset	For this duration the timer will sent sync bytes after startup to allow the microcontroller to sync and not jump directly to the current user program. This should be long enough for a user to press the reset button of the microcontroller to enable flash writing	1s
/serial/write/eepromBurstDelay	Delay between every EEPROM send burst (can be 0 if there is no eeprom)	100ms
/serial/write/flashBurstDelay	Delay between every Flash send burst	10ms
serial/sync/syncByteAmount	Number of sync bytes sent to have a high likelihood of a stable connection	3
/serial/sync/syncByte	Byte value used for synchronization	0xCC
/serial/sync/preamble	Preamble used to signalize the start of user data (will be sent directly after the synchronisation is finished)	0x55
/serial/sync/resyncAfterBurst	Is a resync needed after one burst of data?	true
/binary/format	Format of the binary file	Intel Hex
/binary/unusedFlashByte/	Byte used to signalize that the following flash data is unused (Microcontroller dependent)	0xFF