linux下使用两个串口的问题
omap上有两个串口,一个用作调试口,一个用于跟无线网卡进行通信。
现在kernel中配置了两个串口,kernel启动时的信息也显示两个串口都配好了:
[ 4.331357] Serial: 8250/16550 driver, 3 ports, IRQ sharing disabled
[ 4.343966] serial8250 serial8250.0: unable to register port at index 0 (IO0 MEM1c42000 IRQ25): -22
[ 4.369574] serial8250.0: ttyS0 at MMIO 0x1d0c000 (irq = 53) is a 16550A
[ 4.399265] serial8250.0: ttyS1 at MMIO 0x1d0d000 (irq = 61) is a 16550A
[ 4.800505] console [ttyS1] enabled
starting pid 123, tty '': '/sbin/getty 115200 ttyS1
ttyS1作为调试口,为了测试跟无线网卡通信的ttyS0,在cpu管脚将txd和rxd短接,然后向ttyS0发送一个数据,却收不回来,请专家帮忙看看是哪里出了问题,谢谢!
>echo 1 >/dev/ttyS0
>cat /dev/ttyS0
>cat serial
serinfo:1.0 driver revision:
0: uart:16550A mmio:0x01D0C000 irq:53 tx:40 rx:4 CTS
1: uart:16550A mmio:0x01D0D000 irq:61 tx:16372 rx:564 RTS|CTS|DTR
RFH0-0>echo 2 >/dev/ttyS0
RFH0-0>cat serial
serinfo:1.0 driver revision:
0: uart:16550A mmio:0x01D0C000 irq:53 tx:43 rx:4 CTS
1: uart:16550A mmio:0x01D0D000 irq:61 tx:16372 rx:564 RTS|CTS|DTR