问题
I have a problem with my new bluetooth HC-05 module. In AT-mode it works perfectly with all commands that I need... exept INQ. I have tried to send whole bunch of other commands beforehand:
AT+INIT
OK
AT+ORGL
OK
AT+ROLE=1
OK
AT+CLASS=0
OK
They all are working just fine. I tried to change IAC and INQM settings as well... but the answer from module is always the same:
AT+INQ
ERROR:(1F)
I read related topic here and tried to push the button at HC-05, as it recommended there, but -- no result either. I have three modules from the same shop, and they all are working the same way
回答1:
I have a HC-05 with 3.0-20170601 that I managed to bind to a slave last night. It turns out that the v3 has two AT-modes.
The first is when you hold the button while you connect power. The led will blink slowly and you can connect at 38400 baud. But this is like a configuration mode, where AT+INQ is not available.
In this mode I did these commands:
AT
AT+UART
AT+RMAAD
AT+ROLE=1
(Press and hold the button)
AT+RESET
(Release the button after device restarts and led is slowly blinking)
AT+CMODE=1
AT+INQM=0,5,5
AT+PSWD="9999"
AT should give OK as answer to know connection is working
AT+UART will show configured baudrate. Default is 9600.
AT+RMAAD clears all saved connections
AT+ROLE=1 sets it as master
AT+RESET restarts the device to change to master
AT+CMODE=1 accepts all kinds of devices
AT+INQM=0,5,5 inquires in standard mode, with 5 max connections or 5 secs
AT+PSWD="9999" sets the pin code 9999, change to the pin you need
After this it is time to update the arudino code so that it connects to the configured baud rate. It will be something like
BTSerial.begin(9600);
...or what ever value you might have set the baud rate to. Then reflash your arduino.
Now enter the very irritating second AT command mode.
Power up without holding the button. You will get the fast blink speed. When its powered up, press and hold the button. The led will continue blinking fast, but while the button is pressed you can now connect to the device on the configured baud rate. So open the serial monitor and type AT to verify. Remember that the mode is only active while the button is pressed. So keep it pressed. I had a small clamp I put on there.
Then I entered these commands:
AT+STATE
AT+STATE will show current state, should be inquiring
Then power up the slave device and the adress should start popping up. It will be something like xyz:xy:xyzw,931F00,7FFF
The first part is the address you want (xyz:xy:xyzw)
Change : to , and get xyz,xy,xyzw
Check that you connecting to the correct device
AT+RNAME?xyz,xy,xyzw
Then bind
AT+PAIR=xyz,xy,xyzw,5
AT+BIND=xyz,xy,xyzw
AT+LINK=xyz,xy,xyzw
The AT+LINK command gave me FAIL as output. But it did not matter. I restarted and did not press any button before or after. Just normal start.
After 5-10s serial data showed up in my serial monitor.
Modules are bound. And will automatically connect at power up. If not you might have the wrong pincode. Make sure to change 9999 above to 0000 or 1234 or what ever it may be. When I hade the wrong pin I still got OK from the AT+PAIR and AT+BIND commands... It didnt work for me until I entered the correct pin.
Sorry for long post, but I wanted to be thorough since info about HC-05 v3 is very scarce on the internet right now.
A reference to all commands can be found here: http://www.electronicaestudio.com/docs/istd016A.pdf (Link valid 2018-08-13)
回答2:
We have same problem and you can see the answer in here.
The conclusion of problem is about the firmware on HC-05 you use. If you use firmware version 3.0, you will get error 1F in AT+INQ. Maybe HC-05 with firmware version 3.0 has different parameters to run AT+INQ. Now I'm confused about how to find HC-05 with firmware version 2.0. That HC-05 have push button or not.
In short, the answer is: The (B) module with firmware version 2.0-20100601 works ok with the following commands (set PIN34 high at power-up, or press button on module and keep pressed during commands).
So HC-05 with version 2.0 use push button or not, it's the same.
If you have some information about the different between HC-05 version 3.0 and version 2.0, please let me know.
来源：https://stackoverflow.com/questions/47010342/bluetooth-hc-05-sending-error-1f-for-inq-command-only