ADC value in buffer

[cyril2399]

Posted on August 25, 2011 at 16:49

Hello,

I have a buffer char buf[128];

And when I use ADC it gave me values like 1204 for eg. by ADC1ConvertedValue[1] which is the channel 1 for me.

How could I store the 4 characters 1,2,0 and 4 into my buffer?

I have tried buf[1]=ADC1ConvertedValue[1];

but this store only the first character which is normal.

thanks

[Tesla DeLorean]

Posted on August 25, 2011 at 17:08

Presuming ADC1Converted is an array of integers, of range 0-9999, a quick binary to decimal-ASCII conversion.

buf[0]='0' + (char)(ADC1ConvertedValue[1] / 1000);

buf[1]='0' + (char)((ADC1ConvertedValue[1] / 100) % 10);

buf[2]='0' + (char)((ADC1ConvertedValue[1] / 10) % 10);

buf[3]='0' + (char)(ADC1ConvertedValue[1] % 10);

buf[4] = 0;

http://www.amazon.com/Programming-Language-2nd-Brian-Kernighan/dp/0131103628

http://www.amazon.com/Primer-Plus-5th-Stephen-Prata/dp/0672326965

http://www.amazon.com/Absolute-Beginners-Guide-C-2nd/dp/0672305100

[cyril2399]

Posted on August 26, 2011 at 09:40

thanks clive.

I understand that the first four are for 

thousand,

hundred

,decade,

unit

but for what buf[4] = 0;

is used for?

I don't understand the last...

Thanks

[Tesla DeLorean]

Posted on August 26, 2011 at 15:07

The 'buf[4] = 0;' is used to create a NUL terminated string, so you can use other standard C string functions to copy, concatenate, etc the 'buf' content.

It would permit things like puts(buf) to work.

http://en.wikipedia.org/wiki/C_string

http://cplus.about.com/od/learningc/ss/strings.htm