ttl logic造句

• Because the signal which serial interface output of mcu is ttl logic level , it is essential to transform ttl electrical level to rs - 232 electrical level when the mcu is communicated with pc . in this paper the universal rs232 / 485 electrical level converting circuit board is designed . it can realize data transmission by the two communication level manner
  因为单片机的串行输出接口输出的电信号是ttl电平，这样在和上位机通信时需要通过转换电路对其电平进行转换，所以在本课题中设计了通用的rs - 232 485电平转换电路板，可以实现两种不同电平的数据传输，通过最后的实验验证，该电路板能实现所要求的功能，传输信号可靠准确。