共阳数码管和74HC595芯片连接如下图所示,执行下列程序后,数码管显示的图形为?( )
void setup() { pinMode(32, OUTPUT); pinMode(33, OUTPUT); pinMode(34, OUTPUT); digitalWrite(34,LOW); shiftOut(32,33,MSBFIRST,0xAB); digitalWrite(34,HIGH); digitalWrite(34,LOW); }
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