grove.cxx: drop ADC resolution to 10bit for calculation

Signed-off-by: Brendan Le Foll <brendan.le.foll@intel.com>
This commit is contained in:
Brendan Le Foll 2014-09-10 15:42:00 +01:00
parent d97ce2378b
commit bbb7aa5a39

View File

@ -79,8 +79,9 @@ GroveTemp::~GroveTemp()
int GroveTemp::value () int GroveTemp::value ()
{ {
int a = mraa_aio_read(m_aio); int a = mraa_aio_read(m_aio);
a = a >> 2;
float r = (float)(1023-a)*10000/a; float r = (float)(1023-a)*10000/a;
float t = 1/(logf(r/10000)/3975 + 1/298.15)-273.15; float t = 1/(log(r/10000)/3975 + 1/298.15)-273.15;
return (int) t; return (int) t;
} }