Have got this new device.
Should be a HC-06 BT.
https://www.trab.dk/da/breakout/155-hc-06-bluetooth-serial-pass-thru-module.html
As seen on my photo it says Power 3,6-6V. and that is ok for my 16F18877 ( 5V )
but the levels for signal says only 3,3 V,, how could i fix that ?

 

hi FC
I use these modules.
https://www.amazon.co.uk/dp/B01GKSUST8/ref=pe_3187911_189395841_TE_3p_dp_1

E

 

then i will need a 3.3 v power also ?

 

hi,
I solder a TS2950 [TO92] on the top of the level shifter PCB, it picks up the 5V and 0V pads, to give a low drop out 3.3v.
The level shifter pin 3.3V becomes an output pin for any other small 3.3v devices.
E

 

the 3.3 v is only for driving signal to and from BT module,
Could i just provide a 10k and a 20k resistor in series from 5v to ground, and get 3.3 from the"middle" ?
if use 0.125 W resistors i got 125/5 = 25 mA, should that be enough ?

 

hi,
I know the 3.3v is only for the logic levels, but if you try get a Voltage source from 10k and 20k a resistive divider to drive the level shifter module, due to its high impedance, the I/O logic signals will modulate each other.
You need a low impedance Voltage source to power the module.

Going from 5v to 3.3v with a logic signal, it is possible to use a 2k and3k3 resistive divider to drop it down from 5V to 3.3v.
It is the 3.3v to 5v level shift direction that can cause problems.

Do you have 3.3V reg on the bench that you could use.

EDIT:
I have used a 10K pull up to +5v on a 3.3v logic output pin, so that the input to the MCU senses a logic High.

E

 

Could you simply switch to 3.3V PIC?

 

3.3v pic is possible but have other components that run 5v

Have ordre a 3.3 v ps

 

Just to clarify.
use 16F18877.
Have look much at the datasheet, and as i can understand, the TX/RX pin could be the same ??
That i find strange,
I think i need one for sending data to BTModule, and 1 for recieving from BTModule.

 

hi,
I have searched Microchip for the d/s. it reports unavailable.?
E

 

Hello,

@ericgibbs , The datasheet can be found here:
https://www.microchip.com/wwwproducts/en/PIC16F18877

Bertus

 

Hi Eric,
Here is a link to the PIC16F18877 on the Farnell website. It took a long time to download. I thought it was not going to work. Just a note on the HC-05/6 Blutooth modules. All of the ones I bought a few years ago required a 3.3 V supply but on another thread recently there was a link to some that had a jumper to select between 3.3 and 5 volts. I have always used them interfacing to 5 volt logic. I just used a potential divider to the Bluetooth RX. For the TX from the bluetooth I just added a 3.3V zener so the internal pullup resistor on the input to the PIC or Atmel micro could not pull the Bluetooth TX pin to +5 volts.

Les.

 

Hi,
@bertus,
I still just get 'not available', I will try the 'Les' link to Farnell, I do have an Account with them.
Thank You.
Eric

Edit:
Downloaded it, 648 pages long!.

 

Hello,

@ericgibbs , Here is it attached.

Bertus

 

hi FM,
Ref your post #9.
This clip from the d/s explains that you have to set the TX/RX pins page #555

 

So if i set ASynchronous mode, i will need an Input and an Output pin ? right ?
RX(Recieve) is set to Pin RC7 (default) Could use any B or C Ports.
TX (Transmit) is set to Pin RC6 (default) Could use any B or C Ports.

 

hi,
I would suggest that you use the defaults, RC6 and RC7, most PIC's have those pins for the USART.
E

 

Looking at the right hand picture of your Bluetooth module I think the components at the connector end form a 3.3 volt regulator. The larger PCB with the antenna on the end is the main Blutooth part which will run on 3.3 volts. (It is probably an HC-05 or 06 module.) This a picture of the pinout.


You could check if the pin shown as the 3.3 volts supply in the picture has 3.3 volts on it. If it does you could tap off this to power the level converter board that Eric linked to in post #2

Les.