3750 switch doesn't show text

[cisummer1]

Hello,

I am looking for help with 3750 switch

I console the switch and turn it on and it doesn’t show text in hyper terminal with any BAUD (I tried all the speeds).  The hyper terminal works with other switches so the problem is not with the hyper terminal.

when I tried to break the password it stuck after I was writing "flash_init" and when I entered or typed text it show only garbage characters. I tried to break the password with all the speeds and it shows garabage output.

I tried to turn on the switch and hold control + break and it showed the text only with the speed 115200, but after I left holding and tried to type it showed only garabage again..
I think tried everything! Also I tried to copy text from the notepad to the hyper terminal.

What can be the problem?

Thanks for the help

[Bilal Nawaz]

Hello, can you please double check this...

Baud rate: 9600

Data bits: 8

Parity: None

Stop bits: 1

Flow control: none

The baud rate might have been changed in the confreg... If you are able to boot in to rommon you can do this:

rommon 1 >confregConfiguration Summary 
enabled are: 
break/abort has effect 
console baud: 9600 boot: the ROM Monitor

do you wish to change the configuration? y/n [n]: y
enable "diagnostic mode"? y/n [n]:
enable "use net in IP bcast address"? y/n [n]:
enable "load rom after netboot fails"? y/n [n]:
enable "use all zero broadcast"? y/n [n]:
disable "break/abort has effect"? y/n [n]:
enable "ignore system config info"? y/n [n]:
change console baud rate? y/n [n]: yenter rate: 0 = 9600, 1 = 4800, 2 = 1200, 3 = 2400
4 = 19200, 5 = 38400, 6 = 57600, 7 = 115200 [0]: 0change the boot characteristics? y/n [n]:
           
Configuration Summary
enabled are:
break/abort has effect
console baud: 9600boot: the ROM Monitor

do you wish to change the configuration? y/n [n]:
           
You must reset or power cycle for new config to take effect.

Note: 
On some routers the console speed has been changed in the           configuration register, and a bits-per-second speed of 9600 does not work.           However, this situation is not common. Valid speeds (other than 9600bps)           include 1200, 2400, and 4800 bps. On some platforms, notably the 3600 Series           Routers, 19200, 38400, 57600 and 115200 bps are supported. Try these if you           fail to connect with the settings described in this document.

 Console Session Not Accepting Key Strokes 
This issue can be due to any of these reasons:
Difference in baud rate and the bits per second           value
Bad console cable
Scroll lock option is enabled on the keyboard (make sure that the scroll lock key is disabled on the Keyboard)

Hope this helps.

Please rate useful posts and remember to mark any solved questions as answered. Thank you.

[cisummer1]

Thanks for your comment!

I tried this properties (baud rate:9600, data bits:8, Parity: None, stop bits: 1, flow control: none) like you says but it doesn't show anything in the hyper terminal. It is works with other switches...

Can I get into rommom in a different way or it is happen only when the switch turn on?

And also about the rommon mode I didn't exactly understands the steps, what I have to type and what are the text that I will see?

[Bilal Nawaz]

Hello, we can try this:

Take the power cable out

Hold down the mode button located on the left side of the front panel, while you reconnect the power cable to the switch.

Release the Mode button after approximately 15 seconds when the SYST LED turns solid green. When you release the Mode button, the SYST LED blinks green.

Then we will be entered in to rommon mode.

The prompt should look something like this:

Switch:

From here, can we try typing in the following:

Switch:
Switch: Unset BAUD
Switch: Set BAUD 9600

Once you have done this, you may want to close hyper terminal and reopen with correct baud rate.
Then reset the switch

Switch: reset

Hope this helps

Sent from Cisco Technical Support iPhone App

[cisummer1]

I also tried this.. at the first time I tried it works and I worte "switch: flash_init" but after that it stuck  in the sentence "stti.." and in others time it show the full sentence "setting console baud rate to 115200" but after that I can't typed anything case it shows me garbage output, and I also tried to change the baud to 115200 and it didn't work…

Later I tried it again and it didn't show me anything when I leave the mode button. I tried it with all the speeds.  when I tried to type something it shows me garbage output

When I hold cntrl+break and copy the sentences from the notepad I can see the text but can't type anything.

Will it help if I wiil copy the sentences you says from the notepad to the hyper terminal?

What can else I do??

thanks!!

[Bilal Nawaz]

Okay, can we try to type in "unset BAUD" when we enter rommon mode the first time please?

We want to set the BAUD rate to default which is 9600.

Yes, would be good to see the output when you try this...

Please rate useful posts and remember to mark any solved questions as answered. Thank you.

[Alessio Andreoli]

Set XModem and upload another working IOS image

Alessio

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