I use an HC05 bluetooth-uart module to connect a [Lenovo M10HD](https://www.lenovo.com/it/it/tablets/android-tablets/lenovo-tab-series/Tab-M10/p/ZZITZTATBBX?cid=it%3Aaffiliate%3A97765v&nid=tt&clickid=zqSRor265xyOR7DwUx0Mo3EUUknRpmTYC0HFxQ0&Program=3832&pid=1408424&cid= en: affiliate: copxyq) tablet to an arduino board.
I have a problem: the tablet cannot find the HC05 module ....
The lenovo uses a bluetooth 4.2 protocol ...
How can I solve it?
I tried with a samsung tab-a tablet and recognizes the HC05 module ...
Check the Lenovo spec. BT4 should be backwards compatible by simply reverting to bluetooth2, but that doesn't mean to say that it is. It may be down to the operating system, it may be down to the particular BT4 module it uses.
thank you all for your reply...
Do you recommend a bluetooth module, similar to the HC05 module and compatible with bluetooth 4.2?
I found this I think it's fine.
The HC05 module that I used, I had a button to put the module into programming and receive the AT commands
How do I get into programming for the HM-10 module?
That is an HM-10 as suggested. It is in AT mode 9600 baud by default, and commands are similar to HC-05. HM-10 is not a drop-in substitute for HC-05, even if it looks like it is. You may find there are limits on the apps you can use with BT4. Check the Martyn Currey website.