BT Ramps 1.4 Problem with pins

Hello I followed the instruction and wired the BT JY-MCU with resistors plugged it in to aux1 like i thought it stated. Where i get confused is when it says you have to connect using the Ardunio mega 2560.Before the module can be used the default setting has to be changed. You can connect to and modify the BT JY-MCU module settings via the Arduino mega 2560 using the pin 10 and pin 9 as Rx and Tx terminals, What does this mean? At first i thought it was referring to ramps 1.4 but pins 10 and 9 are not Rx and Tx any help be greatly appreciated TY.

I believe my problems is i am using D1 and D0 pin in aux1 for TX and RX and i have not set this correctly maybe in firmware some place?

Edited 1 time(s). Last edit at 09/27/2014 11:55AM by hellorous.

Working on theory only...

I presume your trying to talk to your ramp wireless over blue tooth?
ie [reprap.org]

Firstly they have used normal IO lines as serial lines, using software serial library in their setup code. So D1 and D2 are correct.
What they seem to be doing is using this to program the board, setting baud rates and such. This done once... So plug it in on d1,d2 and load up [forums.reprap.org]

Configure the serial parameters as desired, how fast can the modules go? maybe start out slow at 9600

To actually use it you need to connect the TX and RX line to the mega somewhere, since serial 0 is hard wired to the usb to serial converter it would be easier to use serial 2

Serial 1: 19 (RX) and 18 (TX); this is top two pins of aux-4
meant to be Serial 2 16 (TX2) and 17 (RX2) ; this is top two pins of aux-4



Then all you need to do is update configuration.h serial 0 to serial 2 and match the baud rate you set above
see [github.com]

If you have a LCD, disable it for now... there are two other serial ports, but they are normally being used as endstop pins... they can be moved.

Edited 4 time(s). Last edit at 09/27/2014 08:09PM by Dust.

dust is correct. you never hook up bt to a serial port already in use. tx0,rx0 are already in use.

Thanks for input I am using lcd ( i disabled it for now) are you referring to D16 D17 on Aux4(Ramps 1.4) I do not see 19 and 18. Also i made mistake on Aux1 I was using D1 and D0 not D1 and D2 my mistake.

Edited 1 time(s). Last edit at 09/27/2014 11:55AM by hellorous.

Just to add this what do I do if I want the bluetooth and lcd at same time? Kind of stinks if have to lose lcd to add bluetooth.Ty

Edited 1 time(s). Last edit at 09/27/2014 12:55PM by hellorous.

your correct, sorry it was really late when I replied... I had serial 1 and serial 2 location mixed up...

RXD2 Digital pin 17 (RX2) on aux4
TXD2 Digital pin 16 (TX2) on aux4

and its serial 2 for configuration.h not 1...

To keep your LCD going see details on serial ports
see [forums.reprap.org]

Basically you have to move the endstops around to elsewhere by editing pins.h to free up the TX and RX of a serial port you want.

Edited 1 time(s). Last edit at 09/27/2014 08:13PM by Dust.

Ok so I read your link on whats is what now say I wanted to use Y min and Y max as new serial due to Z being used by a autobed leveling switch. Can you explain a little farther on the process with editing the pins.h to switch to 2nd servo since 1st is being used by servo motor for arm on autobed leveling? I am new to this part so any help is greatly appreciated. Plus thanks already for that info helped me a lot in understanding what I was trying to do.

I only use Y min atm no Y max.

So for you I would move Y min to X max position, as it sounds like x max and y max is not in use.

So the pins go from being x min,x max,y min,y max,z min,z max to to x min,y min,TX3,RX3,z min,z max

edit pins.h, originally (from the online version )
Line 600 #define X_MIN_PIN 3
Line 601 #define X_MAX_PIN 2
Line 606 #define Y_MIN_PIN 14
Line 607 #define Y_MAX_PIN 15
Line 612 #define Z_MIN_PIN 18
Line 613 #define Z_MAX_PIN 19

Make it
Line 600 #define X_MIN_PIN 3
Line 601 #define X_MAX_PIN -1
Line 606 #define Y_MIN_PIN 2
Line 607 #define Y_MAX_PIN -1
Line 612 #define Z_MIN_PIN 18
Line 613 #define Z_MAX_PIN 19

Then remember to update

configuration.h #define SERIAL_PORT 0 to #define SERIAL_PORT 3

Compile, upload, move you y-min plug over to the x-max pins. Plug your BT into the two S pins of what used to be y-min and y-max, not + or - pins.

And cross your fingers... it should all work.

Edited 4 time(s). Last edit at 09/30/2014 03:44AM by Dust.

You are correct I do not use any endstops for max X,Y, and Z. Thanks for the info will work on it in little bit. You rock A+ thanks for all the help.

Please let me know if this work as expected, and ill update the wiki with this info.

I had no luck atm. Does X and Y max both get set to -1?

yes. it mean no pin. if you don’t do that it will be set as an IO pin, and cant be used as a serial port.

Edited 1 time(s). Last edit at 10/01/2014 04:19AM by Dust.

Dumb question but for vcc and gnd on bt do i use Y min? + and -. Also what pins do i put in for bt_magic since we changed it to 2 and -1.Rx and Tx. One more thing in bt_ magic thing it says softserial2 is that a problem since i am 3 or is it just something different.ty still trying.

Edited 1 time(s). Last edit at 10/01/2014 07:36AM by hellorous.

Making progress I got it working on ymin and y max and connecting to pronterface I will need to wire it into printer tonight just have mega2560 and ramps setting on table atm. Will update later if all goes well which it should....lol

Excellent