Datasheet

Codebase Revision: 0.3.0

Parameters: This command accepts a set of comma-separated key-value pairs that are used to define the

characteristic properties. The following key-value pais can be used:

UUID: The 16-bit UUID to use for the characteristic (which will be insert in the 3rd and 4th bytes of the parent

services 128-bit UUID). This value should be entered in hexadecimal format (ex. 'UUID=0x1234'). This value must

be unique, and should not conflict with bytes 3+4 of the parent service's 128-bit UUID.

PROPERTIES: The 8-bit characteristic properties field, as defined by the Bluetooth SIG. The following values can

be used:

0x02 - Read

0x04 - Write Without Response

0x08 - Write

0x10 - Notify

0x20 - Indicate

MIN_LEN: The minimum size of the values for this characteristic (in bytes, min = 1, max = 20, default = 1)

MAX_LEN: The maximum size of the values for the characteristic (in bytes, min = 1, max = 20, default = 1)

VALUE: The initial value to assign to this characteristic (within the limits of 'MIN_LEN' and 'MAX_LEN'). Value can

be an integer ("-100", "27"), a hexadecimal value ("0xABCD"), a byte array ("aa-bb-cc-dd") or a string ("GATT!").

>=0.7.0 - DATATYPE: This argument indicates the data type stored in the characteristic, and is used to help

parse data properly. It can be one of the following values:

AUTO (0, default)

STRING (1)

BYTEARRAY (2)

INTEGER (3)

>=0.7.0 - DESCRIPTION: Adds the specified string as the characteristic description entry

>=0.7.0 - PRESENTATION: Adds the specified value as the characteristic presentation format entry

Response: The index value of the characteristic in the custom GATT characteristic lookup table. (It's important to keep

track of these characteristic index values to work with the characteristic later.)

As of version 0.6.6 of the Bluefruit LE firmware you can now use custom 128-bit UUIDs with this command.

See the example at the bottom of this command description.

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Note: Key values are not case-sensitive

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Make sure that the 16-bit UUID is unique and does not conflict with bytes 3+4 of the 128-bit service UUID

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