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SUN SPARCstation 2 - serial console garbled after OS start?

Denniske1976

Experienced Member
Joined
Jan 17, 2011
Messages
480
Location
The Netherlands
Hi guys,

I have a little issue with my SS2 (kinda hard to explain in good English, but at least we still have the photo's): I picked up another SS2 (and a very cool SS20 with 2 CPU's) after "that other SS2" seemed to have memory mapping problems. So now I had this one, obviously RTC battery was dead, so I fixed that. Weird thing I have now with this one is that (again, don't know if I'm explaining this right) boot works OK, until I get to the part after "loading vmunix" and getting to the login prompt, at that point the screen gets garbled:

Screen Shot 2022-02-20 at 19.38.00.png

Weird thing is, blindly typing in commands seems to work (of course the output is also rubbish)... so "ls -la" shows something (I also can't read), "reboot" show something (unreadable) and the system reboots and again all of the POST is OK and after "loading vmunix" and "uncompressing" the screen goes weird again, then I login as root (and I don't need a password for some reason but happy that way) and again "shutdown -h now" does stuff and I can turn the system off. I wanted to get into the system to find the host ID from the boot log (as it doesn't seem to be on the orange sticker with this system, there's just a number on it and nothing that looks like a host ID).

I'm using a serial connection (as I always do with SUN systems) and haven't seen this happening before, not on any of the Ultra's I have and not on the Fire v440 or SS20. I was thinking maybe the serial jumper (RS432 and not RS232?) but wouldn't I see weird stuff before getting to the Solaris part (at least I think it's Solaris, the SS20 I got has Aurora Linux on it but it has a password so I either have to reinstall that one or find a way to get to edit the password file).

Anyone here have an idea? Thanks in advance, Dennis
 
Hi Dennis!

I have similar issues with my SPARCstation IPC & IPX. What terminal program are you using? I currently use these two setups from Linux:

1) minicom: serial port is configured with 9600 7E1 (7 data bits, even parity, 1 stop bit).

2) screen: screen -T vt100 /dev/tty...

I use 1) when I want to enter PROM, i.e I need to send BREAK over the serial port. Haven't been able to figure out how I can do that with 2). Once SunOS/Solaris is booted up, I can't enter anything though. If I just want to boot straight into the OS, I use 2).

My suspicion is that maybe the serial port config is switched to something other than 7E1 when the OS boots, but haven't had the time yet to verify this.

Alex
 
Just a guess, but maybe Solaris re-configures the serial port to a different baud rate?
 
Hi Dennis!

I have similar issues with my SPARCstation IPC & IPX. What terminal program are you using? I currently use these two setups from Linux:

1) minicom: serial port is configured with 9600 7E1 (7 data bits, even parity, 1 stop bit).

2) screen: screen -T vt100 /dev/tty...

I use 1) when I want to enter PROM, i.e I need to send BREAK over the serial port. Haven't been able to figure out how I can do that with 2). Once SunOS/Solaris is booted up, I can't enter anything though. If I just want to boot straight into the OS, I use 2).

My suspicion is that maybe the serial port config is switched to something other than 7E1 when the OS boots, but haven't had the time yet to verify this.

Alex
Hi Alex,

This is the First SUN that gave me this "issue", although as mentioned below (well, above) I never had anything pre-SunOS 5.9 installed on one of them (I got them this way). I'm using some program on my MacBook Air, I think it's called SerialTools or something, works perfectly with one of those USB to RS232 adapters (and the right driver).

I have the same problem as you, trying to figure out STOP+A... never got anything working, I thought it was because of lack of a DEL key etc on the MacBook Air keyboard, but I've tried almost all combinations I could find online (even MAC specific). So whenever I need to get into PROM I just connect one of the keyboards I have and I can still use the serial console on Port-A to see where I'm at.

I'll try switching to 7E1, I just have the standard 9600 8N1 and that always worked (so maybe that's the problem on my very old HP 9000 E35 server as well, serial should work and I have that MUX thingie with the serial/modem ports on it but connecting to CONSOLE with just 9600 8N1 never gets me anything on screen -> SerialTools on my Mac).
 
I have the same problem as you, trying to figure out STOP+A... never got anything working, I thought it was because of lack of a DEL key etc on the MacBook Air keyboard, but I've tried almost all combinations I could find online (even MAC specific). So whenever I need to get into PROM I just connect one of the keyboards I have and I can still use the serial console on Port-A to see where I'm at.

The equivalent of STOP-A on the serial console is BREAK. This is not a keyboard combination (well, unless your terminal program has a hotkey for it). A proper terminal program will have a way to send this.

I'll try switching to 7E1, I just have the standard 9600 8N1 and that always worked (so maybe that's the problem on my very old HP 9000 E35 server as well, serial should work and I have that MUX thingie with the serial/modem ports on it but connecting to CONSOLE with just 9600 8N1 never gets me anything on screen -> SerialTools on my Mac).
I'm not sure about the E35 console but a number of UNIX systems require hardware handshaking before they'll enable a terminal on a serial port. Some will output but not accept input, others just do nothing. If it were me that's the first thing I'd check.
 
Well, 7E1 don't make it better... still the same. I checked the readable output a bit and made some screenshots... there's an "invalid format code in NVRAM" error and I see the system type set to Sun 4/60 and afterwards to Sun 4/75 if that makes any difference? The ethernet address and hostid are of course a bunch of ffs because I haven't set that yet (but that shouldn't make for the issue with unreadable output). Oh and it's SunOS 4.1.1 btw:

It also says "The IDPROM contents are invalid", but I did set the NVRAM defaults (except the hostid and ethernet address):
Screen Shot 2022-02-21 at 22.09.28.png

And here I login as root (you can make that out) and "ls -la" gives me output but also unreadable:
Screen Shot 2022-02-21 at 22.10.12.png

So uhm, any other ideas? Can't be that hard to get serial output from SunOS in readable form? Any help/ideas are appreciated! Best from Dennis
 
Based on the last screenshot, it's a character-set issue. It's certainly no random corruption. No idea what could cause this, however.
 
You really need to go in and reset your NVRAM. For the sake of your own sanity uninitialized bits in the NVRAM will cause all sorts of issues and that also includes trying to bring the system up with no hostID or MAC address.
 
Well, set the NVRAM and ethernet/hostid. Doesn't make any difference (I did find out I can send a BREAK signal with screen though, so I learned something). All the errors are gone but still after loading vmunix everything goes weird, also in screen so it's not the Terminal program I'm using. Guess must be some locale or something but since I can't read anything from the (blind) commands I enter I guess I have to go dig up that monitor from storage and see what comes up there.
 
Wow not seen that before. Are you sure the cabling is 100%, ie no dodgy connections? Default serial on my S2 is 9600-8-N-1 by the way. If you can boot the system - port B can sometimes be used to login so you could see if it has the same problem.
 
From the way it's garbling in the first screenshot (shape is right, a few correct characters, we can even recognize the canned text it's trying to show in the big message in the middle, and garbling of individual input characters is consistent)
you have a terminal set to the correct speed but set to 8-n-1 when it should be set to 7-e-1:

The canned text we expect for that message in the middle, for ref
Code:
*** FINAL System shutdown message from root@<hostname> ***
System going down IMMEDIATELY

System shutdown time has arrived

Comparing what we expect to what we're seeing, with hex values for ISO 8859-1
Code:
hex ex act hex  input bit count
53  S  S   53   even
79  y  `u  f9   odd
73  s  o'  f3   odd
74  t  t   74   even
65  e  e   65   even
6d  m  i'  ed   odd
67  g  ,c  e7   odd
...
(i.e. symptom: for any character with odd bit count, the high bit is getting flipped)

But in the later screenshots we can literally see on your screen that 7 bit mode is set and yet it is still producing high characters -> there are gremlins on the terminal side, either in the SerialTools or the OS or the RS232 interface

Since ultimately OS X is some kind of Unix I would use stty on /dev/cu.usbserial and see if changing the setting in your terminal program is even changing the parity setting of the serial port, to decide which thing to proceed trying next (if it is, find another RS232 adapter, if not, replace the terminal software something that actually works)
 
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