University ProgramsのトピックRe: Demo code questions

Demo code questions

jefff — Tue, 03 Sep 2013 23:21:35 GMT

Can anyone explain where the value for ADC_MAX_CODE came from (I want to use this for another function I am doing with the ADC that has different limits and I need to understand where this came from)?

#define ADC_MAX_CODE (4095)

…

//Pot Reading is Scaled to return a value of -1.0 to 1.0

float TFC_ReadPot(uint8_t Channel)

{

if(Channel == 0)

return ((float)PotADC_Value[0]/-((float)ADC_MAX_CODE/2.0))+1.0;

else

return ((float)PotADC_Value[1]/-((float)ADC_MAX_CODE/2.0))+1.0;

}

Question2: I am unable to use TERMINAL_PRINTF for printing out floating point numbers in the Code Warrior demo code FRDM-TFC_R1.0.zip ? Has anyone had any success?

Jeff

Re: Demo code questions

odedyishay — Wed, 04 Sep 2013 00:17:34 GMT

We are using mbed, and the TERMINAL_PRINTF function prints floating points numbers correctly.

-Oded

Re: Demo code questions

craigs — Wed, 04 Sep 2013 00:20:36 GMT

The equations and ADC_MAX_CODE value make sense if the ADC result is being read by the driver in 12-bit single-ended mode.

Re: Demo code questions

jefff — Wed, 04 Sep 2013 00:27:32 GMT

Ah, that makes perfect sense now. Thanks Craig.

And Oded. Yes, I found that %f works using mbed, but not in Code Warrior. I am using CW right now because I had trouble getting the demo code to work correctly for mbed.

Re: Demo code questions

danielhadad — Wed, 04 Sep 2013 02:48:00 GMT

Jeffrey, I'll try to check in an update to the FRDM-TFC library-- checking it out now. Looks like it works at least confirming with Excel-- haven't checked with Labview.