I feel that it is more designed to talk to other devices that is the same as itself ie. another HC08 rather than an external device such as a mobile phone/tablet etc. Many of the commands are unavailable (even though the spec sheet does list all the usual commands?) and it'll nearly always reject 'AT' calls once you've customised it a bit.

In low power mode, if no operation after activating the module, it will return to the low power mode set by the user after x seconds. Note: turn off the LED with instructions and turn it on again. The module will not take effect until it is reset If the module is in the connected state, then after awakening, it will remain in the full speed mode. Before connection, module will return the original power mode. Input: AT+CINT=? Return:OK+CINT=6,12 (Query the minimum connection interval is 1.25*6=7.5ms, the maximum connection interval is 1.25*12=15ms) Therefore, it is recommended to send a 10-byte hexadecimal code "0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF" to wake up the module, avoiding the first few garbled bytes.

Serial . print ( "Slider ID: " ) ; 94 Serial . print (sliderId ) ; 95 96 Serial . print ( "\ Value: " ) ; 97 Serial . println (sliderVal ) ; 98 acc = 99 map (sliderVal , 0 , 200 , 80 , 255 ) ; 100 } 101 // changing between steering and auto 102 mode A. The main low-power mode of module, can provide low-power standby for transparent transmission, and can also be used as low-power broadcast data. Note: The module will restart automatically, and a new operation can be performed after restarting for 200ms!

steering >= 10 ) { 242 turn = map (steering , 10 , 40 , 0 , acc ) ; 243 analogWrite ( ENA , 244 turn ) ; //decrease 245 analogWrite ( ENB , acc ) ; //hold 246 forward ( ) ; 247 248 } 249 if (steering >= 60 && steering <= 90 ) { 250 turn = map (steering , 251 60 , 90 , acc , 0 ) ; 252 analogWrite ( ENA , acc ) ; //hold 253 analogWrite ( ENB , 254 turn ) ; //decrease 255 forward ( ) ; 256 } 257 if (steering < 10 ) { 258 analogWrite ( ENA , 259 spin ) ; 260 analogWrite ( ENB , spin ) ; 261 left ( ) ; 262 } 263 if (steering id I was interested in learning a bit more about BLE a................ if all that is required is to send serial data there is no need to understand Characteristics. It can't be found and can't be connected during sleep. It can be found and connected after activatedby the serial port.

Display Text on an LCD with Bluetooth Using IOS and Android

From that same serial monitor app, I type in a string and send it to the bluetooth adapter on the arduino. It appears in the BLE characteristic FFE0 which is what I want. Keyestudio HC-08 Bluetooth module is a new digital transmission module, based on the Bluetooth Specification V4.0 BLE Bluetooth protocol.