Serial debugging at bootup

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I am trying to figure out what exactly is causing my main computer to reboot itself while booting into BeOS/Haiku. I am booting off of a CD/boot floppy combination: BeOS Max CD and boot floppy with AMD processor fix, IDE replacement drivers, and RAM limiter pre-installed. I have a serial null-modem cable and another machine an I am trying to capture a serial output stream to analyze what is going on.

My problem is, I cannot see any serial output over the serial line. I have enabled serial debugging in the boot menu that pops up when you hit spacebar, and have tried every combination of the other options in that menu to no avail.

The machine listening on the other end of the serial cable is running SerialConnect under BeOS R5. I can successfully talk between the two machines’ serial ports (using HyperTerminal on XP on my main machine, and a serial port test program I wrote on my Be machine), so I know the ports work. Does the serial debug output use different settings than is advertised in the BeOS documentation? From what I’ve read, it should be 115200 bps and 8N1.

I suspect my problem with BeOS is an incompatible chipset, and I’m assuming (probably wrongly) that BeOS can’t communicate with the serial port for the same reason. Does anyone have any experience with serial debugging and can offer some tips? Or, is there a way to have the machine halt instead of reboot when it encounters fatal errors? (that way I’d at least get the last few lines of debug output). Thanks

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I KNOW that Haiku uses 115200 8n1, but I don’t know about BeOS.

For me, if I try to start BeOS R5 with my null modem cable attached and a remote terminal “connected” BeOS doesn’t boot right - and the mouse gets trashed. I figure it’s probably some serial mouse driver causing a problem - so I just yank the null modem cable before I boot into BeOS R5 after using it for Haiku boot.

As for dumping debug output to the screen: a reboot is usually caused by overwriting memory that shouldn’t be overwritten - so there’s not always much the OS can do about that :frowning: You can try using the Pause/Break key on your keyboard at the last second… My guess is that you’re dealing with a driver-gone-bad - possibly video…

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Yeah, it’s generally behaving the way BeOS does if you are trying to boot an AMD processor without the patch (processor freaks out when you call a particular SSE instruction I think it was). My screen is an LCD screen with a relatively long “warm-up” time, and I get about a half-second to read the last page full of debug output on the screen before the machine resets :frowning: If I remember right, there’s a way to log the debug output to a file instead of the serial port, but is it possible when booting off of a CD/floppy combo and not a hard drive?