GATT(GENERIC ATTRIBUTE PROFILE) describes a service framework using the Attribute Protocol for discovering services, and for reading and writing characteristic values on a peer device. There are 11 features defined in the GATT Profile, and each of the features is mapped to procedures and sub-procedures:
| Item No. | Feature | Sub-Procedure | nimBLE command |
|---|---|---|---|
| 1 | Server Configuration | Exchange MTU | b mtu |
| 2 | Primary Service Discovery | Discover All Primary Services | b disc svc conn=x |
| Discover Primary Services By Service UUID | b disc svc conn=x uuid=x | ||
| 3 | Relationship Discovery | Find Included Services | b find inc_svcs conn=x start=x end=x |
| 4 | Characteristic Discovery | Discover All Characteristic of a Service | b disc chr conn=x start=x end=x |
| Discover Characteristic by UUID | b disc chr conn=x start=x end=x uuid=x | ||
| 5 | Characteristic Descriptor Discovery | Discover All Characteristic Descriptors | b disc dsc conn=x start=x end=x |
| 6 | Reading a Characteristic Value | Read Characteristic Value | b read conn=x attr=x |
| Read Using Characteristic UUID | b read conn=x start=x end=x uuid=x | ||
| Read Long Characteristic Values | b read conn=x attr=x long=1 | ||
| Read Multiple Characteristic Values | b read conn=x attr=x attr=y attr=z | ||
| 7 | Writing a Characteristic Value | Write Without Response | b write conn=x value=0xXX:0xXX no_rsp=1 |
| Signed Write Without Response | NOT SUPPORTED | ||
| Write Characteristic Value | b write conn=x attr=x value=0xXX:0xXX | ||
| Write Long Characteristic Values | b write conn=x attr=x value=0xXX:0xXX long=1 | ||
| Characteristic Value Reliable Writes | b write conn=x attr=x value=0xXX:0xXX attr=y value=0xYY:0xYY | ||
| 8 | Notification of a Characteristic Value | Notifications | Write CLIENT CONFIGURATION characteristic |
| 9 | Indication of a Characteristic Value | Indications | Write CLIENT CONFIGURATION characteristic |
| 10 | Reading a Characteristic Descriptor | Read Characteristic Descriptors | b read conn=x attr=x |
| Read Long Characteristic Descriptors | b read conn=x attr=x long=1 | ||
| 11 | Writing a Characteristic Descriptor | Write Characteristic Descriptors | b write conn=x value=0xXX:0xXX |
| Write Long Characteristic Descriptors | b write conn=x value=0xXX:0xXX long=1 |
b show conn
To show discovered services
b show svc
To show discovered characteristics
b show chr
To show connection RSSI
b show rssi conn=x