Re: Ultra 60 won't boot - displays garbage on serial port



John B wrote:
Here's one that I've never run into before.

I recently got a few Ultra 60s. The one works fine. The other, which is set up identically, will not boot. When I connected a VT100 terminal to ttya, I got a bunch of garbage and the system stopped. It never even attempts to boot. I tried it a few more times. The individual characters were predominantly different but the *pattern* of the garbage was almost identical.

Just to be sure, I plugged the terminal into the good U60 and everything came out ttya without a problem.

I've tried a number of different things on the "bad" U60:
- the PROM is good (tried it in the good U60 without a problem)
- tried a large number of different terminal settings (baud, bit length,
term type, stop bit, etc.)
- tried basic troubleshooting (swap CPUs, swap RAM, etc.)
- compared all of the jumper settings with the good U60
- tried Stop+N with no results
- Stop+D *does* display different information, but it's still garbage
- PROM write-protect jumper makes no difference
- Frequency setting is set to the proper CPU type (360 MHz)

Unfortunately, I don't know what if anything I can do further to try to resolve this short of replacing the whole motherboard.

Any ideas?

Try swapping the NVRAM (the one with the orange label) chip with the good machine (After making sure the terminal is set back to the settings for the good machine of course).

If it is some obscure serial port setting, then this will pinpoint that.
If the same machine is still spewing gibberish after the swap, this will point to a hardware problem with that board.

As for fixing nvram if it is the problem, dunno over a serial port. if the machine is sending out data at some unknown serial baud, chances are, its recieving it in the same speed, and Ctrl+N wont do a great deal over a serial line. You may have to yoink a sun keyboard from someone and use that to reset it.
.