Confused by "if" statement in bootloader

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hello,

still learning. trying understand bootloader code. understand registers are, don't understand going on in "if" statement. comparing value of 2 bytes, if equal returns true?

ch = mcusr;  
mcusr = 0;

if ((ch & _bv(wdrf))) app_start();

thanks,

-ren

no, "bitwise and" operator ("&"), typically used isolate particular bit of register.  in case, can read whole segment "if wdrf bit in mcusr register non-zero, start application."


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