aix kernel changes protocol on serial?

UNIX AIX
1

does AIX change the protocol used to transmit over the serial port binded to the system console, during the boot process?

I'm getting no message on the serial port binded to the console, once the control is passed to the kernel. On the LED I have a 0c46 message.

2

Yes, the flow control changes between hardware and sotware just after the welcome to AIX banner.

Your cable should be wired like this:

                                          _________________________
                   5       1             |  DB-9 Side |  DB-9 Side |
        Device    _|_______|_            |____________|____________|
         End     | o o o o o |           | Signal pin | pin Signal |
                  \ o o o o /            |____________|____________|
        Female     / _____ \             |  TxD    3_____2   RxD   |
         DB-9     9         6            |  RxD    2_____3   TxD   |
                                         |  RTS    7_____8   CTS   |
                   5       1             |  CTS    8_____7   RTS   |
        System    _|_______|_            |  DTR    4_____6   DSR   |
         End     | o o o o o |           |             |_1   CD    |
                  \ o o o o /            |                         |
        Female     / _____ \             |  DSR    6_____4   DTR   |
         DB-9     9         6            |  CD     1_|             |
                                         |                         |
                                         |  GND    5_____5   GND   |

                                         |  RI     9     9   RI    |
                                         |_________________________|

BOS install codes:
0c46 Normal installation processing.

HTH

3

yesterday I was able to get a bash on the serial console (ie. the OS completed its boot and I started a session as OS user) with the same cable. So I don't think my problem is related to the cable...

anyway, is there a way to change the mode the OS communicates through the SMS? The machine is not configuring network interfaces, so the console is the only way to reach it.

4

The protocol up until "starting AIX" should all be the same for: install / diag CD / diag boot / single user / open firmware / service processor menu / sms, then it changes.

What do you mean by:
"is there a way to change the mode the OS communicates through the SMS"

You cannot get to SMS through the OS!

SMS is a firmware function.

5

thanks dukessd for the list.

what I meant was: is there a way to alter the operating system communication parameters using the firmware?

I now realize that it isn't probably possible. this morning I was thinking to the firmware/SMS as a sort of grub, through which, even if in a limited way, we can browse the filesystem and pass parameters to the booting kernel.

so my question. thanks a lot for your explication.