HC-05'S Again


Paul
 

I either have the worst luck buying HC-05's... The bluetooth dongle is the last little bit I wanted to get done for my go box, it was a workaround for the lack of band buttons.

I have tried four of them, from two different suppliers and cannot get a response from any of them. I have no problem getting into the programming mode, the 1 second period flash of the led, but cannot get it to acknowledge any AT command.
I am using 8,n,1 no flow control and end the command string with a CR/LF just like the video says

This should not be this difficult.

As I understand it there are some knock off BT adapters that are really HC-06's but I have no way of determining that. In retrospect, I would have been much happier if Elad had offered the dongles for sale or even better yet had incorporated BT into the DUO from the get go.

If anyone can point me to an alternative dongle I would appreciate it. I won't spend another dime on HC-05's
A $5 board against an $1100 radio, come on guys... why couldn't you just have included it

paul
WB9HCO


Fred Lodden <felodden@...>
 

Paul,
I had a similar experience trying to program up my HC-05. I twas very frustrating since following the instructions and the video to the letter did not produce any joy. I just could not get it into AT programming mode.
I even resorted to try programming it with an Arduino Uno and then I tried a Raspberry Pi.. There are articles on the web about how to do that. But even then following all the steps did not produce the result I wanted.
Then just by chance after days of messing around with all sorts of combinations of sequences and steps it worked! I was using the Arduino Uno at that stage.
There is a step where you need to hold the 5V line and the KEY line low and then bring the KEY line high and then after a delay bring the 5V line high, to get into AT mode. Well it was only after not following that step that I was able to get it into AT mode and I was able to program the device. I can't recall the exact sequence. I suggest you mess around with that sequence to see if something different gets you where you want to be.
After that I had a problem where the BlueDuo seemed to be only partially working but a post to Giovanni,revealled that there were a version mismatch between the Elad software and the BlueDuo version I had. A simple update fixed that.
Good luck
Fred
VK2EFL


Giovanni Franza
 

Hi Paul,
which program and which data speeed you used to program ?
If not already done I suggest to use 38400 bps to program the dongle.
In a previous message I posted a step-by-step guide (it could be tedious, sorry):
you can find here:
https://groups.io/g/EladSDR/message/12006?p=,,,20,0,0,0::Created,,hc05,20,2,0,5821789
Since yu do not receive response to AT commands I suggest to verify wiring and speed
(because 8N1-nohandshake-CRLF is ok, and led is flashing)
Hope this can be of help,

Giovanni - HB9EIK


Paul
 

Hello Giovanni

Thanks for the guide, and it's not tedious.
I am using cutecom on a Raspberry pi 3

Going back to basics I pulled out a old TTL pulse probe and checked the TX pin on the pi. I didn't see anything there... this could be due to the probe not being able to see the pulses on the pi output so I'm going to have to drag the scope out and look at the data stream. I have a Siglent 1202 and should be able to decode the serial stream as well as see the raw data pulses. While I am willing to do this I do start to wonder if it's worth the grief...

I have tried both 5V and 3.3v power as I have seen guides using both voltages. Neither one was successful. I do have FDM-S2 running on an notebook. I may just stay there for a while...


Giovanni Franza
 

Hello Paul,
is it possible that, for some reasons, the pi 3 tty is not enabled?
To verify try a "loop" connecting tty input with tty output to see if you receive the echo.
This is a very fasr test to see in there is a problem with the pi3 serial:
Please note that the s3 is a little bit different from the s2: the "good fast hw" serial is connected to bluetooth and the serial is a "poor man" sw one.
This sw UART is not capable to go as fast as 38400, so you be sure that you have switched the fase hw UART out of the BT.
Regards,

Giovanni - HB9EIK


Paul
 

Hi Giovanni

Looks like I'm into the HC05

I had to update the pi and enable the hardware UART.
I disabled the serial console in the pi's config menu.

Do you know how long it's been since I did a loopback test... more old knowledge recovered and that checked out fine.

What was less obvious was selecting /ttyS0 instead of /ttyAMA0 to program the HC05, that discovery was kind of accidental but who cares now :>)

I did this:
*******************
AT+ORGL followed by CR and LF resets the module
the answer must be OK
AT+NAME=BLUEDUO followed by CR and LF sets the name to BLUEDUO
the answer must be OK
AT+PSWD=2357 followed by CR and LF sets the password to 2357 (if you do not do this the default password is 1234)
the answer must be OK
AT+UART=115200,0,0 followed by CR and LF sets the speed to 115200, stop bits to 1 and parity to none
the answer must be OK
****************

and got the correct OK answers, but was not able to communicate with the HC05 after that...


I now have to load BlUEDUO my android and plug the HCO5 into the DUO.

In retrospect I probably should have used a RS232 level converter and just done this on my linux box.


I will let you know how I do, thanks for the encouragement.

-- 
73
de 
paul
WB9HCO

"You see, wireless telegraph is a kind of a very, very long 
cat. You pull his tail in New York and his head is 
meowing in Los Angeles. Do you understand this? 
And radio operates exactly the same way: you send 
signals here, they receive them there. The only 
difference is that there is no cat." Albert Einstein

Resistance Is Not Futile!
It's voltage divided by current.

No trees were killed in the generation of this message,
but a tremendous number of electrons were terribly 
inconvenienced

"To err is human...to really mess things up requires the 
root password."

"If you're not part of the solution, you're part of the precipitate."


On 02/24/2018 11:12 AM, Giovanni Franza wrote:
Hello Paul,
is it possible that, for some reasons, the pi 3 tty is not enabled?
To verify try a "loop" connecting tty input with tty output to see if you receive the echo.
This is a very fasr test to see in there is a problem with the pi3 serial:
Please note that the s3 is a little bit different from the s2: the "good fast hw" serial is connected to bluetooth and the serial is a "poor man" sw one.
This sw UART is not capable to go as fast as 38400, so you be sure that you have switched the fase hw UART out of the BT.
Regards,

Giovanni - HB9EIK