b***i
发帖数: 3043 | 1 看wiki看的稀里糊涂，因为觉得有矛盾，于是把一句话改了，就通顺了。大家看看该得
对不对。
我的理解：A+ /B-
那就是如果发送1， 或者IDLE，A比B高几百毫伏。这个和wiki里面的图，和其中列的各
公司的芯片所述一样。
原来写的是：如果发送1，B会比A高。我改成A比B高。 | i*****t
发帖数: 24265 | 2 At any receiver, a "1", (Idle, Mark, or Stop bit), state is defined when the
voltage on the "B" line is greater than the voltage on the "A" line by at
least 200 mV. A "0" (Space or Start bit), state is defined when the voltage
on the "A" line is greater than the voltage on the "B" line by at least
200mV. Shown in the equations below:
Va - Vb < -0.2V = "1"
Va - Vb > 0.2V = "0"
Where Va and Vb are the voltages on the "A" and "B" lines respectively.
Unfortunately, the "A" and "B" pin labeled on the IC data sheet does not
necessarily have to correspond to the "A" and "B" in the RS-422/485 standard
. | b***i
发帖数: 3043 | 3 我又改回来了
the
voltage
standard
【在 i*****t 的大作中提到】
: At any receiver, a "1", (Idle, Mark, or Stop bit), state is defined when the
: voltage on the "B" line is greater than the voltage on the "A" line by at
: least 200 mV. A "0" (Space or Start bit), state is defined when the voltage
: on the "A" line is greater than the voltage on the "B" line by at least
: 200mV. Shown in the equations below:
: Va - Vb < -0.2V = "1"
: Va - Vb > 0.2V = "0"
: Where Va and Vb are the voltages on the "A" and "B" lines respectively.
: Unfortunately, the "A" and "B" pin labeled on the IC data sheet does not
: necessarily have to correspond to the "A" and "B" in the RS-422/485 standard
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