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MSP430 USI i2c and Adafruit LCD backpack

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Ive had this Adafruit Lcd backpack for a while and thought I would get it working with the launchpad.

I'm using a sparkfun level converter, and I am powering the LCD via the TP1 port on the launchpad.

For the i2c code I used fj604's from here: viewtopic.php?f=10&t=1037

The code sends characters 2 different ways, one char at a time , and using oPossums tiny printf

from here: viewtopic.php?f=10&t=1732

Maybe someone can use this. The code is attached, its a CCSv5 project.



here is my setup



here is the backpack. (I added the led for debugging)



small video(really impressive!)


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  • 2 months later...

I did a quick experiment where I un-commented the serial debug code, which compiled fine, but I got errors when CCS attempted to link the serial.asm object file to the project. Is there additional setup I need to do/make in CCS 5.2 to inform the linker how to resolve the external call to serial_setup?


Also I noted that the print.c module had an exclamation point next to it, not sure what that means?


Thanks great project, lot's of good info on I2C, 3.3 to 5V conversion, etc.





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Thanks for the compliment!!


If you are using the serial.asm code be sure to uncheck the exclude resource from build box in the compiler preferences.

Right click on the serial.asm file in the project explorer click on msp430 compiler then uncheck the box.


I tried to comment everything that needs to be un-commented for the serial terminal to work. That serial code of oPossum's

was a great help in debugging I use it all the time now.


As far as the exclamation point on the printf.c file goes, I think its mostly a syntax thing I have CCS 5.1 and I get

"Possible assignment in condition 'c =*format++'. If it compiled and ran than I guess its not that big of a problem.


This is a good question for oPossum the original author of the code, maybe he will see this and reply, I'm pretty sure

he uses CCS as well.


edit: Ive updated my CCS to ver and I get 6 function declared implicitly warnings when compiling.

Due to the fact that the putc function is declared in the main and not the printf file.

It loads and runs fine.


I hope this helps


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