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您好!tronlong提供的最新的linux3.3内核已经对uart0和uart1做了rs485功能的支持,uart2默认为启动串口。如何想使能uart0和uart1 rs485的功能,只需在menuconfig将485使能。
! S( f; W& x7 S& t1 [ *** DaVinci Core Type *** | |
( U5 _- u0 a; }& K8 t" A# } | | [ ] DaVinci 644x based system | |) `/ t9 B2 V: d' G
| | [ ] DaVinci 355 based system | |
6 j( E% S$ @$ x" ?" q | | [ ] DaVinci 646x based system | |
7 `$ u6 d% }; m% q ] | | [ ] DA830/OMAP-L137/AM17x based system | |' g+ R7 `% h; K0 i- E
| | [*] DA850/OMAP-L138/AM18x based system | |) Q, u4 u( k* {1 U8 W3 D
| | [ ] Enable UART1 flow control | |
+ f. q/ k4 D' V1 } | | [ ] Enable UART0 RS485 funcation | |- j9 S8 i# j! i- F
| | [*] Enable UART1 RS485 funcation
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想了解详细的功能实现,也可以查看8250.c文件里面的;
4 t: K7 g6 g! ?. Y3 S+ |: M7 Yvoid serial8250_tx_chars(struct uart_8250_port *up)+ y' |( P U+ |- f7 A
return;2 s3 A' r W* J" b& ]
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9 w( `5 c/ _5 U' {
+#if 10 c. ]$ p+ |( ?2 t& q/ o
+ /* The funcation with RS485 flow control */
! T, {8 D6 p2 d2 g/ s+ if (up->port.private_data) {
! E) P8 ]8 }( g Z+ struct serial8250_flow_ctrl *flow_ctrl_p;7 P( T, Z- C; g9 Z( b) x
+ flow_ctrl_p = up->port.private_data;
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+ if (flow_ctrl_p->gpio) {
7 m# M: i( h' o8 J+ gpio_set_value(flow_ctrl_p->gpio, 1);" Z6 @' ?. y9 g) D
+ ndelay(50); /* Propagation delay >= 50ns */, |+ p* q- P" U+ L3 N: j& N1 l
+ }
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+#endif' i C4 v) T* ~' V3 u9 v/ D
希望对您有帮助。
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