Controlling HC-05 from a sketch

Question

Hi I am making a sketch and circuit with a HC-05 BT receiver to upload sketches via Bluetooth to my Uno. This requires giving AT commands from the sketch. I would like to see the response from the HC-05 but so far I haven't got it to work. I want to view the response via the standard serial connection and serial monitor. The commands from the sketch are not being recognized by the HC-05 and I would like to see the HC-05 response to troubleshoot it.

If you have a minute would you mind giving me a tip? I would greatly appreciate it. See the ArdProgramModeOn() and Off functions at the end.

Thanks

int ATModePin = 2; // pin for HC-05 AT comand mode
int HC05powerPin = 3; // pin for powering HC-05 when high
char btserialrx; // data through from bt connection
char myChar; // data through serial port connection
#define rxPin 8 // HC-05 bt serial pin
#define txPin 9 // HC-05 bt serial pin
#include <SoftwareSerial.h>
SoftwareSerial btSerial(rxPin, txPin); // RX, TX
void setup() {
 pinMode(ATModePin, OUTPUT);
 pinMode(HC05powerPin, OUTPUT);
 pinMode(5, OUTPUT);
 Serial.begin(9600);  
 btSerial.begin(115200); 
 
 digitalWrite(HC05powerPin, HIGH);
 delay(2000);
 }
void loop() {
 while (btSerial.available()) {
  btserialrx = btSerial.read();
 }
 if(btserialrx == '1'){ // change to upload / reset mode
  Serial.println("switching to upload mode");
  ATModeOn();
  ArdProgramModeOn();
  ATModeOff();
  btserialrx = '0';
 }
 else if (btserialrx == '2'){ // change to normal mode
  Serial.println("switching to normal mode");
  ATModeOn();
  ArdProgramModeOn();
  ATModeOff();
  btserialrx = '0';
 }
}
void ATModeOn(){ // reset HC-05 and change HC-05 to AT Command Mode
 digitalWrite(5, HIGH);
 digitalWrite(ATModePin, HIGH); // AT command mode on upon reset
 delay(2000);
 digitalWrite(HC05powerPin, LOW); // hc-05 off
 delay(2000);
 digitalWrite(HC05powerPin, HIGH); // hc-05 on
 delay(2000);
} 
void ATModeOff(){ // reset HC-05 and return HC-05 to std. operation 
 digitalWrite(5, LOW);
 digitalWrite(ATModePin, LOW); // AT command mode off upon reset
 delay(2000);
 digitalWrite(HC05powerPin, LOW); // hc-05 off
 delay(2000);
 digitalWrite(HC05powerPin, HIGH); // hc-05 on
 delay(2000);
}
void ArdProgramModeOn(){
 btSerial.println("AT");
 delay(1000);
 btSerial.println("AT+POLAR=1,0"); // Arduino reset mode upon HC-05 connection for programming
 delay(1000);
 btSerial.println("AT+POLAR?"); // Arduino reset mode upon HC-05 connection for programming
 delay(2000);
 while (btSerial.available()) { // Show responses from HC-05
  myChar = btSerial.read();
  Serial.print(myChar);
 }
 delay(4000);
}
void ArdProgramModeOff(){
 btSerial.println("AT");
 delay(1000);
 btSerial.println("AT+POLAR=1,1"); // Arduino normal mode no reset upon HC-05 conection
 delay(1000);
 btSerial.println("AT+POLAR?"); // Arduino reset mode upon HC-05 connection for programming
 delay(2000);
 while (btSerial.available()) { // Show responses from HC-05
  myChar = btSerial.read();
  Serial.print(myChar);
 }
 delay(4000);
}

Answer 1

Unless you've manually set the btSerial speed, you need to be at the default for AT commands which is 38400 -> btSerial.begin(38400);

If you want to read regular Serial communication, you'll need to monitor 9600 -> btSerial.begin(9600);

If you are unable to to send commands, I feel as if you wouldn't have changed the default speeds.

I used this link as a reference with my project: Modify The HC-05 Bluetooth Module Defaults Using AT Commands

Lastly, you didn't mention whether or not you soldered a jumper wire to PIN 32 for your ArdProgramOff/On. Another reference for you as well: DIY Arduino Bluetooth Programming Shield

Hope my answer helps! Good luck!

• perigalacticon: Thanks for responding. The Make article is the one I followed to make the setup. I have wires soldered to the HC-05 32 and 34 pins for the reset signal and AT command mode. I pre--programmed HC-05 from the serial monitor to operate at 115200 baud to be able to upload to the Uno. In the example pages you sent the HC-05 and serial monitor are communicating at different baud rates but I guess a buffer handles that difference? Thanks.
• perigalacticon: Basically I'm wondering about the While loops to monitor serial received from the HC-05. I have one at the start of the loop, and then one in both functions (ArdProgramMode...) where I am sending commands to the HC-05 from the Uno sketch. Do you see a conflict in the code here, should this code design work correctly? Thanks.