擅长:python、mysql、java
<p>使用ioctl更改逻辑级别。。。</p>
<pre><code>98 struct serial_rs485 rs485conf;
99
100 /* Enable RS485 mode: */
101 rs485conf.flags |= SER_RS485_ENABLED;
102
103 /* Set logical level for RTS pin equal to 1 when sending: */
104 rs485conf.flags |= SER_RS485_RTS_ON_SEND;
105 /* or, set logical level for RTS pin equal to 0 when sending: */
106 rs485conf.flags &= ~(SER_RS485_RTS_ON_SEND);
107
108 /* Set logical level for RTS pin equal to 1 after sending: */
109 rs485conf.flags |= SER_RS485_RTS_AFTER_SEND;
110 /* or, set logical level for RTS pin equal to 0 after sending: */
111 rs485conf.flags &= ~(SER_RS485_RTS_AFTER_SEND);
112
113 /* Set rts delay before send, if needed: */
114 rs485conf.delay_rts_before_send = ...;
</code></pre>