|
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。% V& t) s1 X3 b% r, k
*** DaVinci Core Type *** | |
; X5 h/ m( C, @, O1 R | | [ ] DaVinci 644x based system | |
. Q. E5 w8 r/ L/ T* Q# U | | [ ] DaVinci 355 based system | |* S' Z, m" G! s% i n
| | [ ] DaVinci 646x based system | |
2 x4 O4 H8 ^+ E | | [ ] DA830/OMAP-L137/AM17x based system | |
0 n8 v; B. S- v! V$ @9 y | | [*] DA850/OMAP-L138/AM18x based system | |
- w9 n( ]! c8 J0 Y$ g3 I+ k | | [ ] Enable UART1 flow control | |; E5 |0 _# n8 Z& [( ?
| | [ ] Enable UART0 RS485 funcation | |
- G0 V; Z$ ~; X9 k | | [*] Enable UART1 RS485 funcation # d- o+ _) z( R- ]$ x4 F, B$ P0 `
( |# d' B' L S) J0 ~8 b- m X
想了解详细的功能实现,也可以查看8250.c文件里面的;
( H" T0 f; I2 h% y3 Z. i kvoid serial8250_tx_chars(struct uart_8250_port *up)
W' j1 \! G* }8 z& @' D return;' V5 U$ f4 F( ]1 ~
}3 y, N9 t$ v9 `, X1 o7 V7 u
; c$ E5 z1 i/ f" A' Q+#if 16 ~6 d2 a; {+ F; Y* E( Y
+ /* The funcation with RS485 flow control */- l; l& m, E6 |. L! f* L# e
+ if (up->port.private_data) {; q$ _6 }% C0 ?7 ?
+ struct serial8250_flow_ctrl *flow_ctrl_p;
$ [" E* A' V+ r: c" r; \( m+ i4 ~1 n+ flow_ctrl_p = up->port.private_data;
% e& m$ Z$ b2 B; d+ V+ s+- F9 M: h6 a8 i$ O* L
+ if (flow_ctrl_p->gpio) {
; j1 N% ?6 y$ O) V/ ?+ gpio_set_value(flow_ctrl_p->gpio, 1);2 m: T5 c; C; b1 s2 r4 D4 a
+ ndelay(50); /* Propagation delay >= 50ns */
% {5 v( M2 {* G1 ?/ z$ Q/ E8 d9 R8 C+ }4 D2 l& I: R, g- i) U' t
+ }
- |! F/ E1 S" q7 d+#endif
( y: j. j7 i+ }: I+ M, u希望对您有帮助。
5 O0 D; O( k g9 ?2 b0 u |
|