| 摘要 |
<p>A non-polarity 485 chip includes a polarity converting switch connected in series to data input/output pins or communication pins of the 485 chip. The polarity converting switch is controlled to switch when a voltage between two communication lines (La, Lb) of the 485 chip is higher than zero and the duration exceeds a predetermined time, thereby making polarity of the lines coincident with internal polarity of the chip. The 485 chip has accurate connection, and is convenient to use.</p> |
