Hi everyone, I really need help with my project. I’m building smart glasses to help deaf individuals. The idea is: I speak into my phone, and the phone translates the speech into text using an app made with MIT App Inventor. The translated text is then sent via Bluetooth to an Arduino Nano, which displays the text on a small OLED screen mounted on the glasses. I’m using an HC-05 Bluetooth module and a 0.96-inch OLED I2C display.
The problem is that I can pair the HC-05 with my phone in the Bluetooth settings, but in the app, it doesn’t connect. When I click the ListPicker, it either shows nothing or gives Error 507. I’ve tried different blocks and setups, but I still can’t get it to connect.Or i personnaly think it can be the device or something in the device
If anyone here knows how to fix this or has worked on a similar project, please help me. I’m stuck and this is important for me. I can also share screenshots or the .aia file if needed. Thank you so much.PLZ help me i my first high school project!!!
for a start rather than using a Nano and HC-05 with all the problems of interconnections I would look at using a module with microcontroller with onboard Bluetooth and display such as the Heltec wifi-kit32
note the V2 uses an ESP32 with WiFi, Bluetooth Classic and BLE the V3 uses a ESP32S3 with Wifi and BLE
what smartphone are you using?
which Bluetooth protocol?
have you tested Nano <> HC-05 communications, e.g. can you run HC-05 AT commands?
have you tested the smartphone <> HC-05 communication using any other app, e.g. using a simple Terminal app on an Android (a HC-05 connected to an ESP8266)
so the thing is the display is working.....And the Nano Im not sure and the HC-05 is paired but is not connecting in the app thats the problem......So i nead the help in checking the nano like you meantion and the connection bettwen the app and the HC-05
never used a Nano with a HC-05 always microcontrollers with hardware serial port, e.g. Due, ESP8266, etc
try changing the thread title to "need help with Nano HC-05 project"
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thinking again I seem to remember the HC-05 uses 3.3V logic, e.g. my HC-05 has "LEVEL 3.3V" against RX and TX pins
the Nano uses 5V logic therefore use a level converter or potential divider between the Nano Tx and HC-05 Rx or you could damage the HC-05 - see Interfacing-HC-05-Bluetooth-Module-With-Arduino
one reason why I tested the HC-05 use an Arduino Due and a ESP82666 both of which use 3.3V logic
And you are just talking round in circles. About 5% of your project is Arduino and the rest is App Inventor. If you can't get the phone to translate speech to text and send it to it's Bluetooth, you are dead in the water and the crocodiles are coming - MIT problem But you do need to first ensure Arduino can receive the message in the vague likelihood of the above being successful - Arduino problem. To do this, all you need to do is have Arduino echo a "hello" to a standard terminal on your phone, like that by Morisch.
Nano + HC-05 is used by a bazillion users and there is no need to change from what you've got.
You might find these basic notes useful. The first few pages may be all you need.
// Nano classic <> HC-05 Software Serial test
// using library instal AltSoftwareSerial
// https://github.com/PaulStoffregen/AltSoftSerial
#include <AltSoftSerial.h>
// for loopback test connect pin D9 to pin D8
// for HC-05 shield connect
// Nano pin D9 TXD to HC-05 Rx (note HC-05 uses 3.3V logic!!)
// Nano pin D8 RXD to HC-05 Tx
// connect GND pins together and VCC to 5V
// NOTE: Tx and Rx pins are 3.3V logic level
// if connected to a 5V logic host (UNO, Mega, nANO, etc)
// use a level converter on host Tx to HC-05 Rx pin
// Connecting to Android phone
// on Powerup HC-05 LED should flash
// using Settings PAIR phone with HC-05
// when paired run Terminal app
// e.g. https://play.google.com/store/apps/details?id=de.kai_morich.serial_bluetooth_terminal&hl=en-US
// set devices to Bluetooth Classic and select HC-05
// enter and receive text
// Set up a new SoftwareSerial object
AltSoftSerial HC_05_serial;//(rxPin, txPin);
void setup() {
// Open serial communications and wait for port to open:
Serial.begin(115200);
while (!Serial) {
; // wait for serial port to connect. Needed for native USB port only
}
Serial.println();
Serial.println("\n\nNano <> HC-05 SoftwareSerial test");
// set the data rate for the SoftwareSerial port
HC_05_serial.begin(9600);
// HC_05_serial.println("Hello, world?");
}
void loop() { // run over and over
if (HC_05_serial.available()) {
Serial.write(HC_05_serial.read());
}
if (Serial.available()) {
char ch=Serial.read();
//Serial.write(ch); // local echo if required
HC_05_serial.write(ch);
}
}
pair HC-05 with an Android phone
run a Bluetooth Terminal app, e.g. Serial Bluetooth Terminal
select HC-05 and transmit/receiver text
e.e. serial monitor output
Nano <> HC-05 SoftwareSerial test
hello from android
test2 1234456789
test3 agfyghjjgffh
For the HC-05 and MIT App Inventor connection issue, check out this project on Manual and Automatic Water Level Controller. It uses the HC-05 with Arduino Nano and MIT App Inventor. The block setup for Bluetooth and ListPicker might help with your connection issue.
