Questions to users of JY-MCU's HC-05 6-pins breakout


Any users of this? |400x300

I would like to know 2 things:

1) The dimensions of the board itself (not counting the pins header). I have a HC-07 and the board of the HC-05 looks a little longer and I need to know how much longer.

2) How to connect and use the STATE and KEY pins? On my HC-07 there is only 4 pins but theere are holes for those 2 pins and they are connected to the BT board, I tried to connect the STATE to an arduino input and read it, but it always read 0, connected or disconnected. Must I use a pullup or pulldown resistor? Or is it just that the HC-0507 doesn't use these pins at all?


The PCB is 15.3 x 35.5 I believe the picture you show is distorted.

I believe this family all use the same PCB. The HC-07 is like the HC-06 and is not normally configured, but the HC-05 is more configurable and has the pins provided for that purpose.

The procedure is available here:

By having both HC-05 and HC-06, I have not needed to configure anything.

Yep image is distorted because I quickly resized it to 400x300, here is correct size:


But see where are the resistors etc next to the pin header, this area looks larger on this picture than on my board (which has the same dimension than yours), maybe like 2mm more. And those 2 mm could be too much.

So do you have exactly the board as shown in the picture? Anyway I will buy it and see, maybe I will be lucky and it will fit perfectly in place.

Thanks for the document but are you sure HC-07 is same as HC-06? I mean there must be some differences but I don't find any datasheet or documents about HC-07...

I was mistaken about the HC-07, I know nothing about it.

I now don't think my PCBs are the same as yours, but this may be of no consequence. What I have:

an HC-06 that came on a 4-pin JY-MCU backboard v1.05.

2x bare HC-05 modules (bad idea)

2x JCY-MCU backboards 6-pin v1.02

I installed the HC-05s myself.

As far as I can see, all my JY-MCU backboards are the same, apart from some paint-marks but there are a couple of extra SMDs on the v1.02 boards. I have no idea what they do and I can't remember if they were specifically for the HC-05, indeed I'm not even sure I knew the HC-05s were HC-05s. Everything works, maybe luck has quite a lot to do with that.