I won't be reading the whole thing if I don't need them right away. Over time, likely when issues are encountered. If you look at the prompt texts when a code is inserted, you will see that the description "putting 3 back ticks" (this part that you put) is missing. This was where the ambiguity started.
Good luck on the forum and for your project.
I’m out, you are too selfish for my expectations.
You may try Tasks-12.2 of the attached file for practicing AT Commands.
Expt-12(PCD) (2).pdf (720.3 KB)
Explained in post#12.
Leo..
You MUST NOT connect a 5V digital output to a 3.3V digital input, without using some sort of logic level shifter. It is an extremely basic rule of electronic devices.
The voltage divider is one form of a logic level shifter. Here is a bidirectional logic level shifter, which is more generally useful:
A thousand people a day can correctly post a sketch, but you can't because of someone else's instructions didn't repeat verbatim information posted all over this forum? Rather than reading some of it some time later, read it all now. Drop the attitude.
Hey, don't do character assassinations. Learn to understand that REAL WORLD has different types of REAL PEOPLE, and each type has a place, not just through yours and my lenses. Seriously, you don't have to be around if you don't want to.
Thanks a lot.
Thanks, teacher!
Thanks for your explanation. Your article is an eye opener to me.
The most obvious reasons for NOT using the 3.3v is that it is contrary to the clearly written instructions on the back of the breakout board.
HC-05 is a 3.3v device. There is already a 3.3v regulator on the breakout board for VCC, hence the "3.6 > 6v", but the Rx pin still needs a 3.3v signal - as stated.
It doesn't matter what power source you use for HC-05, Arduino's Tx signal is 5v.
Don't ask why the module is made like this, but it may well not be made with Arduinos in mind.
If you need to use the EN pin, that can be run off Uno's 3.3v.
Thanks, another teacher.
Related to your explanation, so if I want to run AT commands (just AT, AT+NAME, AT+VERSION at this stage), I would have to connect the EN pin.... I will get resistors to fix the voltage divider issue first.
To anyone with some advice, (not sure if it is less straightforward), I got the HC-05 module from the seller, and I am now in the testing window. My testing window is till 9 Oct. If the product is found to be "ok" from test coverage based on "best-effort basis", the module is considered sold. Payment is a lesser concern than the confidence if the product has a possible chance of working in some applications from GolamMostafa's pdf. Perhaps, won't be ready to run a master/ slave application test for now.
My original test coverage was to connect up and test out 3 AT commands (the 3 mentioned above). Unfortunately for now, my results are mixed. The AT command worked at baud rate 38400 but the AT+NAME and AT+VERSION commands did not. Nothing worked at the baud rate 9600.
My questions are :
(a) how reasonable/ inadequate is my test coverage for some applications ?
(b) if I fix the voltage divider issue and the mixed results persist, there wouldn't be anything "inadvertently left out" that points to module defect right ?
Please, note --
1. For AT commands, the Bd should be set at 38400.
2. For normal operaion with peripherals, the Bd should be set at 9600 if using Software UART Port.
No. the button will do for those. There are more obscure commands for which the button will not suffice and you have to lean 3.3v on either pin 34 on HC-05 or the EN pin. I'm afraid I don't know where the demarcation is, or the difference between pin 34 and EN, if any. More information on this can be found on the Martyn Currey website.
38400 is the ONLY baud rate for HC-05 AT mode.
There are a lot of dodgey HC-05s around. I understand they are all fine so long as you don't use any AT commands. There may be some that give grief with the more obscure commands but otherwise OK. Again Martyn may have something on this.
Also note that, while anybody who knows what they are doing will surely advise you to use the divider on Arduino's TX, only somebody who doesn't know what they are doing will bet you have fried Bluetooth if you didn't. So don't panic. While there is always a first one to fry it, it probably won't be you. I ran my first HC-0x 24/7 for two years without frying it and I have never heard of anybody else frying one, ever. And about half the diagrams on Google omit the divider.
You come here and join a community for help. This community has simple practices to make the forum a nice place to come to for all readers - it’s not a place where you focus only on yourself.
I don’t think it’s such a huge ask for you to read those practices and fix your posts that are missing the baseline.
You’ll also find that doing so will get you faster and better answers.
To your problem I hope you did not fry the module by sending 5V to a 3.3 V logic input…. It’s like sending 350V to a device designed for 230V. Not great. So hard to point the finger at a defect in the module after that. Face the consequences of your doing.
I would be the seller, I would not accept a return when the buyer abused the module.
Figure-1:
1. In Fig-1 of HC-05 Bluetooth Module, 3.6V - 6V is clearly marked near VCC-pin. It means that any voltage of the range 3.6V to 6V cab be safely applied on the VCC-pin of the Module. There is an onboard voltage regulator to derive 3.3V operating voltage for the HC-05 Module.
2. The other pins (RXD, TXD, STATE, and EN) are compatible with 3.3V logic which is also marked on the module. If logic levels of 5V are applied on these pins, the module might get damaged.
3. To interface 3.3V HC-05 device with 5V Arduino UNO, the following connections (Fig-2) are recommended.
Figure-2:
(1) UNO asserts 5V logic on STX-pin. It is brought down to about 3.4V by the R1-R2 voltage divider to be compatiale with RX-pin of HC-05. Here, R1-R2 network works as a Level Shifter.
(2) HC-05 assets 3.3V logic on its TX-pin. This level is very well recognized by UNO as logic high; so, there is no need of any level shifter.
(3) To bring HC-05 into AT Mode, it is reqired to apply 3.3V logic on EN-pin (procedures are in my pdf of post #23). This logic can be applied from the 3.3V-pin of UNO.
OK, reserved for my "advanced learning" 
I did not start by connecting the circuit to a 5V Arduino terminal. I started only by connecting it to a 3.3V Arduino terminal. This was one of the reasons I asked the seller on the differences between the 3.3V vs 5V usage earlier.
Thanks, I had to start concluding that there are many teachers here!