请教android串口通讯的问题


 谢谢提醒，改过来 改成attr.c_cflag = B9600 | CS8 | CREAD; 或attr.c_cflag = B9600 | CS8 | CREAD |CLOCAL 都收不到串口数据打印

解决方案 »

  1.   

    系统 dmesg 打印信息是<6>[2014:05:19 06:51:05] [  462.301446] [5.1 kworker/u:0]max:800000 min:150000 block:0
    <3>[2014:05:19 06:51:11] [  468.178715] [5572.1 sh]gs_write: ttyGS0 (d1efb9c0) writing 3 bytes
    <3>[2014:05:19 06:51:11] [  468.187466] [5572.1 sh][ttyGS0,<<<count=3]
    <3>[2014:05:19 06:51:11] [  468.193343] [5572.1 sh]41 54 0A                                                                                        AT.
    <3>[2014:05:19 06:51:11] [  468.206889] [0.0 in_irq swapper]gs_write_complete:
    <3>[2014:05:19 06:51:11] [  468.213602] [0.0 in_irq swapper][ep1in,<<<count=3]
    <3>[2014:05:19 06:51:11] [  468.220131] [0.0 in_irq swapper]41 54 0A                                                                                        AT.
    <3>[2014:05:19 06:51:12] [  469.251140] [5572.0 sh]gs_write: ttyGS0 (d1efb9c0) writing 3 bytes
    <3>[2014:05:19 06:51:12] [  469.259794] [5572.0 sh][ttyGS0,<<<count=3]
    <3>[2014:05:19 06:51:12] [  469.265904] [5572.0 sh]41 54 0A                                                                                        AT.
    <3>[2014:05:19 06:51:12] [  469.279199] [5572.0 in_irq sh]gs_write_complete:
    <3>[2014:05:19 06:51:12] [  469.285736] [5572.0 in_irq sh][ep1in,<<<count=3]
    <3>[2014:05:19 06:51:12] [  469.292092] [5572.0 in_irq sh]41 54 0A                                                                                        AT.
    <3>[2014:05:19 06:51:20] [  477.210821] [5572.0 sh]gs_write: ttyGS0 (d1efb9c0) writing 8 bytes
    <3>[2014:05:19 06:51:20] [  477.219732] [5572.0 sh][ttyGS0,<<<count=8]
    <3>[2014:05:19 06:51:20] [  477.225918] [5572.0 sh]41 54 2B 43 47 4D 49 0A                                                                         AT+CGMI.
    <3>[2014:05:19 06:51:20] [  477.239632] [5572.0 in_irq sh]gs_write_complete:
    <3>[2014:05:19 06:51:20] [  477.246169] [5572.0 in_irq sh][ep1in,<<<count=8]
    <3>[2014:05:19 06:51:20] [  477.252523] [5572.0 in_irq sh]41 54 2B 43 47 4D 49 0A[2014:05:19 07:00:04] [ 1000.893682] [6480.0 testmux]gs_write: ttyGS0 (d1efb9c0) writing 9 bytes
    <3>[2014:05:19 07:00:04] [ 1000.902569] [6480.0 testmux][ttyGS0,<<<count=9]
    <3>[2014:05:19 07:00:04] [ 1000.909038] [6480.0 testmux]41 54 2B 43 47 4D 49 0A 00                                                                      AT+CGMI..
    <3>[2014:05:19 07:00:04] [ 1000.923202] [6480.0 in_irq testmux]gs_write_complete:
    <3>[2014:05:19 07:00:04] [ 1000.930169] [6480.0 in_irq testmux][ep1in,<<<count=9]
    <3>[2014:05:19 07:00:04] [ 1000.936954] [6480.0 in_irq testmux]41 54 2B 43 47 4D 49 0A 00                                                                      AT+CGMI..
    <7>[2014:05:19 07:00:04] [ 1001.143010] [5146.1 kworker/1:0]:regulator_id 1  BUCK2 OFF 
      

  2.   

    当设置  select(fd+1, &fds, NULL, NULL, &tv) <= 0   第一个NULL为&fds时，程序立刻返回  ，打印信息为 
    ./testmux
    hello, Serial port is OK
    readlength=0有办法检测该串口设备不让直接写么？需要其他方式写