SGI: Hardware

Hello, all.
I'm trying to salvage a non-booting 500/600MHz fuel for a young/kid sgi-enthusiast. I don't know why this fuel's motherboard is missing the L1 serial db9 connector just below the second heatsink, but it's just not there. I figure seeing the L1's diagnostic messages would be helpful. Is there a way to connect this fuel's rear-panel L1 usb type-b port to my working fuel's usb type-a port? I've looked at my /etc/uucp/Devices file and don't see any usb entries, but I do have ttyus N type device files in the /dev directory. Would it be feasible to connect the two fuels using a usb a-to-b adapter cable, add usb entries to the /etc/uucp/Devices file and try something like:
cu -l /dev/ttyus1.
Any help would be appreciated.

Hi,

using the B-type USB port as a serial device will most likely not work, as they are intended to
connect a L2 controller. Besides that there is no support for USB-serial devices in IRIX.
The ttyus* devices are for raw byte access without system calls (see serial(7) ) to generic
RS232/422 ports.

As I see it you have two options:
1.) solder a DB9 connecter to the empty pads on the mainboard, or, probably easier,
2.) use the USB-B connector with an L2 controller (or the L2/L3 software) to access the L1
on the Fuel...

..... you could also try connecting to the numerically lowest (external) serial port.

Never had a Fuel without the DB9 L1 port on the system board (so I haven't had a reason to try this myself), but it seems likely SGI would have provided some method to access the L1. I'd try it first with the serial terminal configured at 9600/8/N/1, then at 38,400/8/N/1 if that doesn't work.

If you get PROM/console access, try a combined "control t" key press and see if that switches you to L1 mode.

I can confirm that connecting to the COM1 port on a Fuel works. That's how I normally do it.