HC-06 Fails

[Tnixsw]

Hi,

I have used 100's of these devices mainly to connect microcontroller projects to a PC, Win7, 10 and 11. Up until recently, I have only had the odd faulty module, but in the past month or so, I have ordered 50 from various vendors and none work, which I find odd.

They will accept AT commands, and they will pair to the PC. However, they will not communicate via the serial interface. I know Win 11 requires a setting change to make them work, but all 3 Win versions have always worked reliably in the past. Now none of them do.

These modules come in two varieties, one with a Blue LED on board, and one where you have to connect an external LED. The Blue LED type work every time, but the other type does not. I can swap a blue LED type in place of the faulty unit, and it also works fine.

Talking to a vendor is like talking to a brick wall, so I was wondering if anyone else is using these and is finding similar problems.

cheers

[eTobey]

Why not posting pictures? Have you measured the signals with a scope? Have you tried a smartphone? Do the other old modules still work now?

[eTobey]

However, many sellers are now shipping BLE-only modules while still calling them “HC-06”. These often use the JDY-XX, BK3266, CC2541, or BT06 family of BLE chips.

Omfg good to know...

[Tnixsw]

Thanks for the responses.

There is BC417 marked on both the Blue LED and external LED boards, although the Blue LED version always has a smaller sized chip.

I can read the version as "linvorV1.8" on the faulty units

I did receive a response from one vendor who said they were "updated" versions, whatever that means. However, whatever the update was, they now fail to work.

If they do not have SPP protocol, I'm not sure what their purpose is anymore, and why then have a baud setting.

cheers

[Buriedcode]

Different versions have different firmware, that have different default baud, and syntax for AT commands.

This guy seems to have done extensive work with them:
https://www.martyncurrey.com/the-complete-guide-to-the-hc-06/

As you have so many I ugess the best way would be to order form a bunch of places till you find one that "behaves" - itherwise I would have suggesting flashing different firmware on them with a CSR dongle from aliexpress.

I much prefer the HC-05, which also has "fakes" and different firmwares, but tend to be more reliable.

I'll second the request for a photo of the ones you have

[Tnixsw]

Thanks again for the reply

I attached an image of the HC-06 modules. I marked 2 missing components on these boards, but seeing as it pairs ok, I guess they are not needed.

I recently received another couple on HC-06's with a HC-05 from yet another vendor. I could use the HC-05 fine (with minor mods for connections), but the 2 HC-06's still had the same problem. As mentioned, the AT commands work fine, I can change the baud rate and the communicate with more AT commands in the new baud setting, and it pairs and sets up a COM Port on the PC.

When I start my Win application and select the COM Port that was allocated for the HC-06, the LED stops flashing and stays on indicating that the link is active. If I close my PC app, the link is broken and the LED starts flashing again which is normal. It's just the serial comms do not work on any of these boards.

The trouble with searching for working units, is the time it takes with no guarantee that the next batch you buy will work, (+ the $ involved). I tried to ask specifically for the Blue LED variety which always work, but the vendors cannot guarantee sending them. I bought 2 separate lots of 20 modules, only one had the blue LED, which worked fine, the other 39 didn't work. Maybe I'll just have to give up on them and use something else. I tried JDY-31, but the ones delivered were in a simple plastic bag and I could not get them to work at all. As indicated, maybe more HC-05's or maybe HM-10, but I'll need patch boards to connect them to my current boards.

[Buriedcode]

Just a thought - have you tried these rogue HC-06s on different host platforms? Android? Linux? 

I ask because for a long time, windows' bluetooth drivers were janky at best.  Whats worse, is, the CSR drivers that are recommended with the HCxx series have a bug where it adds an extra termination character (null) to the port name - so some host applications cannot connect to the port.  Sometimes they appear to connect, the part of the host app that connects correctly gets the port names, ignores the extra character and the module appaears connected, but the part that actually handles coms doesn't, so nothing gets sent or collected from the buffer.

Its a long shot, but I had this issue with windows 10 and HC-06 (and HC-05 for some time).  I had to completely uninstall the CSR harmony driver, and the windows one and let windows take over for it to create functional com ports.

Note HM-10 being BLE are compeltely different and I couldn't get them to work on any version of windows I have.  They do however, work fine on Android.

[Tnixsw]

@BuriedCode, thanks for the reply

I'm definitely no expert, but I'm not sure it is a Windows problem. (and it could be of course)

My old Win 7 machine has been sitting unused and disconnected from the internet for some time, but it used to work fine with HC-06's. Now, unchanged from that state, it does exactly the same thing, it pairs ok but will not transfer serial data.

I thought maybe a bad batch of modules were produced, but I have been lurking around arduino/reddit sites and searching for HC-06 faults, but I am not seeing any reports of this issue. It could be just me, but I cannot figure out why these particular modules won't work, especially as I purchased from different vendors and HC-05 and Blue LED HC-06's do work.

I think I will try sticking to HC-05 in slave mode for now or maybe try the likes of Microchip RN4871 or similar.

thanks

[Andy Chee]

Here's a silly question;

Why fuss over purchasing HC-05 versus HC-06 in the first place?

For the hobbyist, I would thought a HC-05 would be more versatile as it can act as master or slave.  It's not as if there's a significant cost saving between the two!

[Tnixsw]

> Why fuss over purchasing HC-05 versus HC-06 in the first place?

All my circuit boards are designed for HC-06. I just had some adaptor boards made up though, but if I need more boards, I will make them able to use both.

I received another 2 new HC-06's today and tried one out. It programmed and paired fine which I expected. However, just after it paired like it normally does after entering the password, a new window popped up that I have never seen before asking me to log into the device. Being unsure, I tried the password again, the screen went away briefly but then came back, so as I was thinking, What does it actually want?, it disappeared and never came back. Hmmm. I powered up my hardware and got it to turn the module on - LED flashing. I then started my win app, selected the assigned COM Port and bingo it worked. Ok great, but what about the faulty ones I tried previously. I fished out one of the many faulty? HC-06's and soldered it onto a new board, programmed and paired it, and it now works also.

This sort of points to a Windows problem, maybe the drivers were changed on the Win update which coincidently ran earlier today, or the HC06's I just got triggered something in windows, I don't know.

cheers

Tony
 

[Buriedcode]

With one connected to your PC, you should be able to view the driver name/manufacturer/version in device manager.  Sounds like a standard windows driver, but there are other (CSR/Qualcomm) that might not behave properly.

I also noticed over the years that when windows 10 updated, it radically changed how it handles bluetooth devices, mulitple times - not just minor updates.  What version of windows are you using?

[Tnixsw]

I also noticed over the years that when windows 10 updated, it radically changed how it handles bluetooth devices, mulitple times - not just minor updates.  What version of windows are you using?

Win 10 Home, Version 10.0.19045

[Buriedcode]

Same as one of my work PCs - I'll ahve to dig out a HC06 and see if it has a blue LED or not and test it 

[rteodor]

If it helps, this is my very first try with this HC-06 modules (from Olimex, BC417).
I put one on a UART-TTL adapter and it appeared dead in the beginning: no LED activity at all, consumption cca. 160uA.

After quite a few "try this - try that" I got it to work by connecting all 4 wires while in the background I had minicom open (@ default 9600) and also writing these AT commands in a loop:

Code: [Select]

for s in $(seq 0 100); do echo "AT" >> /dev/ttyUSB1; sleep 0.2; echo "AT+VERSION" >> /dev/ttyUSB1; sleep 0.5; done
LED's blinking. Open SerialTest app on the phone and LED's are ON. Typed data is passed correctly between minicom and app.

[Tnixsw]

These modules can be fine or a headache. Flaky module manufacturer/supplier, flaky windows, maybe flaky new projects and software they are used with.

Either way, sources of faults can be hard to trace.

I'm not 100% sure if Win 10 is the culprit, as my old non updated win 7 machine failed also, when previously it worked fine.

Thanks everyone, appreciated.