evm ballot unit info.txt

8051单片机 a51 投票器 带控制端 含原理图

port 1: votecast LED panel

port 2: candidate panel


candidate's 4-bit long code : p0.0, p0.1, p0.2, p0.3 (transmit to control unit)




ready signal: p3.4(receive frm control unit)

vote signal: p3.5(receive frm control unit)

buzzer: p3.6

machine ready LED: p3.7




p0.4-p0.7: no connection
p3.0-p3.3: no connection


imp: ground of control unit must be connected to ground of ballot unit


connect p0.0, p0.1, p0.2, p0.3 of ballot unit to p2.0, p2.1, p2.3, p2.4 of control unit, respectively