Gilles Piantoni

M52233DEMO - ADC in differential mode

Discussion created by Gilles Piantoni on May 30, 2007
Latest reply on Jun 8, 2007 by Maclain Lobdell
Hi everyone,
 
I've a little question about the ADC module (using M52233DEMO board).
In single ended mode, everything's allright. The result of the conversion is correct, but in differential mode, when AN0 = AN1, AN2 = AN3, AN4 = AN5 and AN6 = AN7, all results are about 0x4008 instead of 0. Here's my registers values:
 
PANPAR = 0xFF; //All pins in AN mode
CTRL1 = 0x00F5; //Differential mode + Triggered + Parrellel
CTRL2 = 0x0023; //Simult + DIV (=/16)
 
ADLST1 = 0x3210; //Sample 0 = AN0, Sample 1 = AN1,...
ADLST2 = 0x7654;
 
ADSDIS = 0; //All samples enabled
 
POWER = 0x00D4; //Power up delay + Reference auto
CAL = 0; //Using VRH and VRL pins
 
Any idea ?

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