PIC18 and Easy Bluetooth

[carlozofjuan]

Hello everyone! I am trying to resolve an issue involving my PIC18F2550 and Parallax Easy Bluetooth module.

I am using a PIC and the Easy Bluetooth module to communicate with my PC and having trouble, but I do get a response in 2 ways.

The first way, I shorted the Rx and Tx pins on the Bluetooth and was able to echo back what I have sent to it from Hyper Terminal or the Serial Communicator feature Mecanique MicroCode Studio.

The second way is I have managed to have the PIC send bytes through the Bluetooth to Hyper Terminal or Serial Communicator. With the latter, I am able to tell that the PC is receiving the correct number of bytes (if a carriage return is indeed a bit).

The problem is the characters are not the string I sent from the PIC nor do they have a pattern that reflect the string I sent. Example, I send "hello" from PIC-Bluetooth and receive something like "pxpxx" choosing "Force to 7-bit ASCII" in Hyper Terminal. Not choosing the option shows the characters from an extended set.

I did a PIC to PIC async serial communication test and found it to be working fine. One PIC sent a string out the hardware transmit async pin to the hardware receive async pin of the receiving PIC and then outputted the received string to LCD and successfully displayed the characters.

Assuming the problem is not with the PIC, or maybe just treat the PIC as if it were a STAMP for minute, I wonder what is going on when a string is transmitted from a PIC/STAMP to the Bluetooth if/how the string is altered when it leaves the Bluetooth to be received by the PC.

Just to clarify, I am using the Easy Bluetooth module that has one PCB attached to another that only has the Vdd, Tx, Rx, and Vss pins that go into my breadboard.

I'll post the code used as well as the sample program that is available as free download to accompany the Parallax Easy BT module. Any insight is very appreciated!!

Current code "eBT_hello.pbp" written in PicBasic Pro:

' -----[ I/O Definitions ]-------------------------------------------------

RX          Var     portC.6                     ' RX of the Easy Bluetooth

TX          Var     portC.7                     ' TX of the Easy Bluetooth

CR          con     13

 

' -----[ Constants ]-------------------------------------------------------

 

Baud      CON     84        ' Baud set at 9600

 

' -----[ Variables ]-------------------------------------------------------

 

myByte    VAR     Byte      ' Byte to establish connection & used for workspace

 

 

DEFINE HSER_RCSTA 90H

DEFINE HSER_BAUD 9600

DEFINE HSER_CLROERR 1 ' ? MAY NOT BE IN PBP2.32

'DEFINE CHAR_PACING 65000

 

 

RCSTA.4=0 ' CLEAR ANY ERRORS CREN BIT

RCSTA.4=1 'START RECEPTION 

RCSTA = %10010000       ' Enable serial port and continuous receive

 

 

' -----[ Initialization ]--------------------------------------------------

 

' The Easy Bluetooth Module is waiting for a Byte to establish connection;

' press any key in the TOP window pane of the DEBUG or PST to do this.

 

PAUSE 250                                           ' Waits 5 seconds

 

main:

hserin 1000, main, [myByte]                            ' Waiting for byte

myByte = 0                                          ' Clear the byte value

 

' -----[ Program Code ]----------------------------------------------------

 

hserout [ "Hello", CR]        'CR carriage return is 13

Is based on:

' =========================================================================

'

'   File...... Easy Bluetooth _ Hello.bs2

'   Purpose... Displaying uni-directional communcation with a PC & Bluetooth

'   Author.... Technical Support & Education

'   E-mail.... support@parallax.com

'   Started... Jan 16th 2009

'   Updated... April 1st 2009

'

'   {$STAMP BS2}

'   {$PBASIC 2.5}

'

' =========================================================================

'

'

' -----[ Program Description ]---------------------------------------------

'

' This program displays a bi-directional communication between the Easy Bluetooth

' and a Terminal Window.

'

' -----[ Revision History ]------------------------------------------------

'

' revised 4/1/09 for the new Easy Bluetooth module

'

' -----[ I/O Definitions ]-------------------------------------------------

 

RX        PIN     2         ' RX of the Easy Bluetooth

TX        PIN     0         ' TX of the Easy Bluetooth

 

' -----[ Constants ]-------------------------------------------------------

 

Baud      CON     84        ' Baud set at 9600

 

' -----[ Variables ]-------------------------------------------------------

 

myByte    VAR     Byte      ' Byte to establish connection & used for workspace

 

' -----[ Initialization ]--------------------------------------------------

 

' The Easy Bluetooth Module is waiting for a Byte to establish connection;

' press any key in the TOP window pane of the DEBUG or PST to do this.

 

PAUSE 250                                           ' Waits 1/4 second

SERIN RX, Baud, [myByte]                            ' Waiting for byte

myByte = 0                                          ' Clear the byte value

 

' -----[ Program Code ]----------------------------------------------------

 

SEROUT TX, Baud, ["Hello", CR]

 

[azoma]

please i want to connecct easy bluetooth modue to whiteboard and no action even i tried to connect tx to rx and my pc can't send or revieve file for easy bluetooth module my pc said BL doesn't support file transfer i tried to check them on the configuration of easybluetooth on the pc but no use

 

[carlozofjuan]

Hello Azoma,

I was not able to resolve my problem with the Easy Bluetooth module so I returned it for a full refund. Instead I purchased something else that seems to work better but I haven't used it in a project yet. It's called Toothpick by Flexipanel. https://www.flexipanel.com/Docs/Toothpick%20DS380.pdf

Good luck!

 

[Mike_2545]

you forgot

DEFINE HSER_TXSTA 24h