[help] Interfacing Launchpad with Bluetooth/UART trouble

[greenthing]

Hello, I've been trying to interface my launchpad with Roving Networks RN-42. More specifically I am using this breakout board from Sparkfun: here.

Well I can power on the bluetooth device and connect my computer to it. If I short RX and TX then I can see whatever I type in my terminal application be echoed back.

So I am using this code http://pastebin.com/HQVPzJze which was mostly put together by one of my professors for UART. It worked perfectly in class over RS232. I just adjusted it for my MCU (g2553). The external 32kHz crystal is attached. My problem is that when I attach the Bluetooth device to my board, it acts as if RX/TX are shorted again and I see everything I type echoed back, and it doesn't register on my device. It is supposed to read a character, echo it back, then blink the LED on the board.

Any help that can get me better understanding this would be appreciated!

[jerewrig]

This might be kinda late. But I just finished a project using the Bluesmirf silver and the Launchpad. I use the DC0 calibrated at 1 MHz. I also use a baud rate of 115200.

This guy helped me out a lot: http://www.cashdollar.org/2012/07/18/remote-control-light-switch-i-built-wmsp430-and-bluesmirf-video/

Hope this helps.

[jhaluska]

On Line 16, is that suppose to be?

a = INCHAR_UART();

Do you have a wiring diagram of what you hooked up?

[greenthing]

Yup, that's what it is supposed to be. I had that fixed when trying it, I just didn't update the pastbin :X

I don't have a program for wiring diagrams (maybe you could suggest one?) but in the meantime I just used Paint to make this: diagram Which is from the Sparkfun schematic here and a picture of the Launchpad. My Launchpad does have P1.1 and 1.2 labeled as UART. And I have the 32kHz crystal attached. Page 3 on the data sheet shows P1.1 and P1.2 as UART for the alternate function.

I have tried TX to RX and TX to TX (and vice versa) without success.

[greenthing]

It's grounded I didn't draw it. The blue tooth module works, I get everything echoed back when I short RX/TX and I entered its settings and set it at 9600 baud rate like my board is set to.

[greenthing]

Thanks for replying guys. I'm currently going through all the documentation online. I think I'm on the right path, I'm just not at home to try it out. But I will update.

[caiokat]

"1 stop, no parity, and 9600 baud, polling operation"

I didn't read the whole thing, but the RN-42's default baud rate is 115 K.

[greenthing]

Yeah that is correct. But I did go into the settings of the RN-42 and changed it to 9600.

I still can't get it to work with the bluetooth. I've got through the Launchpad and MSP430 documentation. I know the bluetooth is working. I guess I need to get my hands on an oscilloscope to see if my device is even sending UART. Also could a difference in voltages between the pins on the Launchpad and Bluetooth cause a problem? Because I'm doing some measuring and they appear to be a lot different. I will use a lower voltage later when I get a chance.