ESP32 - Wrover - AT Instruction - BLE - message data length
Posted: Fri Feb 07, 2020 7:56 am
- I configured my Wrover device to work with AT commands as server BLE.
- Client recognize BLE server, its connect to Wrover and send/receive information on BLE stream.
- This sequence to start service:
- AT+BLEINIT=2
- AT+BLENAME="BLE_SERVER_1"
- AT+BLEGATTSSRVCRE
- AT+BLEGATTSSRVSTART
- AT+BLEADVSTART
- Default data length (received and transmit message) is set 23 bytes (20 data + 3 control) and may be enlarged until 517 (514 + 3 control bytes).
- When client is connected, its change this configuration setting MTU to another value (503, for example), this mean that Wrower can send message until 500.
- Unfortunately size of Wrover receive buffer doesn't change (20+3 bytes)
- When client send Wrover a message bigger than 20 GATTS, Wrover answer an error message (the attribute value length is invalid for the operation).
- I don't know how enlarge this characteristic.
- I've use AT+BLEDATALEN but Wrover doesn't manage it (return ERROR).
- I think that its settable with AT+BLEGATTSSETATTR but i don't know how manage it.