|
|
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。
7 \# l2 b0 k& Z4 Z. T *** DaVinci Core Type *** | |7 t) E4 S! O2 F: s; @# Q
| | [ ] DaVinci 644x based system | |
4 G: s" F# D! \5 ]! d! h; A% r | | [ ] DaVinci 355 based system | |0 d! v; U! n2 q/ T0 D
| | [ ] DaVinci 646x based system | |
1 Z: ^- T( H% A, p; |; S | | [ ] DA830/OMAP-L137/AM17x based system | |
+ {* u6 G! s6 I' \ e' x | | [*] DA850/OMAP-L138/AM18x based system | |$ \& j, w, V/ z8 X" Y
| | [ ] Enable UART1 flow control | |
0 V; Z9 R- ]: n; I2 t% Y; }5 L | | [ ] Enable UART0 RS485 funcation | |3 M% B& w N# F5 @
| | [*] Enable UART1 RS485 funcation
$ R4 y9 v, t. p; p' u. n
+ N7 B( C1 a. M" h; J) W5 p想了解详细的功能实现，也可以查看8250.c文件里面的；
& G* _, T/ ` Q6 ~void serial8250_tx_chars(struct uart_8250_port *up)3 N; n( ~4 G* \% k9 I
return;. q" {9 a3 J( C! `/ H- i
}+ N; h' x0 V$ _: o- f
! l- }# Y5 |7 A$ y. o1 K/ H6 H8 O4 ^
+#if 1
( S/ t/ l3 Z9 ?/ q! \, X+ /* The funcation with RS485 flow control */5 i8 m3 C! Z# R1 Y
+ if (up->port.private_data) {% ]* [+ S6 f" h6 W9 J) S3 p+ N
+ struct serial8250_flow_ctrl *flow_ctrl_p;& y) j1 b4 f0 f4 Q3 A* z2 W
+ flow_ctrl_p = up->port.private_data;8 U# u7 N3 J( p6 p; A
+
9 G( f* @% M: j4 i7 Y8 \% ?/ n+ if (flow_ctrl_p->gpio) {
' G9 M3 X* W" y" \: y5 t+ gpio_set_value(flow_ctrl_p->gpio, 1);) O+ [- h) W( }9 k* z
+ ndelay(50); /* Propagation delay >= 50ns */
2 D1 i0 r) F9 v) i% U" L1 E5 j+ }) S! M2 a' T, w) Q7 Y
+ }# C: f4 h {) x2 ~0 Y) U$ t
+#endif) Q7 U8 i f; p3 |3 a K
希望对您有帮助。
' f* }7 l# R; |5 W |
|
|手机版|小黑屋|嵌入式开发者社区
( 粤ICP备15055271号 ) 
发表于 2014-10-31 17:01:26
QQ好友和群
QQ空间
腾讯微博
腾讯朋友
收藏
淘帖
楼主