ADC example project of f28335

Leon,

I'm not sure about the ControlSuite code you are citing.  Download the code with appnote SPRA958:

http://www.ti.com/mcu/docs/litabsmultiplefilelist.tsp?sectionId=96&tabId=1502&literatureNumber=spra958l&docCategoryId=1&familyId=1414

There is starter code for F28335 there.  It will run on the Experimenter kit (read the appnote section describing the code).  It is simple code, and will convert ADC input ADCINA0 at a 50 kHz rate.  Results are continuously placed in the circular buffer ADCBUF.  You can view this in the watch window or a memory window.  Run the code, then halt, then observe the ADCBUF values.

You can test the ADC channels in your device one by one (to check that each channel is working correctly) by modifying the InitAdc() function in file adc.c.  You'll see what to do.  The code is well commented.

Regards,

David

Hi, David,

I downloaded it.  The project is easier and very helpful, though took longer time to import into CCS.   I'll use this as a starter code.  But I'm still curious about the question I saw before.   Thanks a lot!

Best,

Leon

Leon,

Leon Jin said:

I downloaded it.  The project is easier and very helpful, though took longer time to import into CCS.

What version of CCS are you using?  The project code in the appnote version on the web is for CCSv5.3.0.  It should load right up into CCSv5.3.0 or later.  If you're using an earlier version of CCS, then yes, you would have to create a new project.

Leon Jin said:

But I'm still curious about the question I saw before.

Tough to say.  I'm not familiar with that program.  It's possible that your device is damaged (just a possibility).  You can use the SPRA958 program to test each ADC channel.  Could be user error.  Again, tough to say.  My opinion - just work with the new program and move on (as long as the device is not damaged).

Regards,

David

Leon,

One question that may lead to your answer on the AdcSoc project:
When you view the watch window, what do you see on AdcRegs.ADCRESULT0 & AdcRegs.ADCRESULT1?

(these AdcResult values should be 12-bit ADC values left justified within a 16-bit register)


Thank you,
Brett

Leon,

I use CCSv5.4.0 too, and run these projects constantly.  They should not cause any problems or make any changes to your CCS installation.

It sounds like an emulator connection type problem.  Instead of clicking the green "Bug" icon in CCS (which launches the debugger and downloads the code), instead just launch the target configuration manually (right-click the configuration in the Target Configuration window and click 'Launch selected configuration', something like that).  Then after launching, try connecting to the target (Run->Connect_Target).  Does it connect?  If so, reset the target and try to step a few lines of code (the ROM bootloader).  Does it step?  Can you change RAM contents in the memory window?

The code security module in the F28335 could give these types of connection problems, but if you only ran the RAM examples from the appnote there is no way you could have programmed the code security module passwords.  That would require you to use the flash examples and also you'd have to deliberately modify them to set the passwords.

- David

Leon,

In addition to Brett's suggestion to look at the ADC result registers, you said that you convert with "A2 suspended." I interpret this to mean that you commented out some code from the original example to disable channel A2?  If so, can you specify which lines have been disabled? 

Devin,

Thanks for your reply.  Actally, I did nothing to A2, nor the code.  I mean A2 is not connected to anything and the code is still the original one.  I'll look at the result registers.

Regards,

Leon

David,

I reinstalled  CCSv5.4 and it's working well now.  I saw others also meet this problem. So it shouldn't be caused by your code.  Thanks for your help!

Best,

Leon