do...while exiting when it shouldn't?

i think loop exiting when shouldn't...here's code...

code: [select]

    int contact_new = 0;
    int contact_old = 0;
    int changepoint = 0;
    int livelog = 0; //(set 0 contact change log)
    int rval = random(50,255);
    int gval = random(50,255);
    int bval = random(50,255);
    int p=0; //pixel number;
    float start = millis();
    long total1;
    long total2;
do {   

do {
total1 =  cs_4_2.capacitivesensor(1);
total2 =  cs_4_6.capacitivesensor(1);
if ((total1 < 15) && (total2 < 15)) contact_new = 0;
if ((total1 > 15) && (total2 < 15)) contact_new = 1;
if ((total1 < 15) && (total2 > 15)) contact_new = 2;
if ((total1 > 15) && (total2 > 15)) contact_new = 3;
   serial.print ("no change");
   serial.print ("\t");
   serial.print (contact_new);
   serial.print ("\t");
   serial.println (contact_old);
   delay(500);
}while (contact_new = contact_old);
 
  serial.print ("input valid, processing");
  serial.print ("\t");
  serial.print (contact_new);
  serial.print ("\t");
  serial.println (contact_old);
  delay(1000);

it's part of it...as far i'm aware, should keep getting total1 , total2 values, based on conditions exit loop "input valid" stage if contact_new different contact_old.

but without changing on pins in question, processes "input valid" command, when both contact_old , contact_new zero.

what doing wrong? if need code let me know, though i'll have edit some...

code: [select]

    float start = millis();
why? millis() not return float.

quote

what doing wrong?

1) not posting of code.
2) not posting serial data.
3) not printing enough data. proof inner do/while loop being exited prematurely useful.

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