[ ... how PROM 'console' variable works ... ]

| The screen went blank and all the LED turned on when I
| input:
|
| >> setenv console s
|
| Why?

Because your PROM monitor reset the serial hardware circuit at the
moment, then switched PROM i/o to the serial port.  If you hooked a
9600N8 terminal with your DECstation, you would have PROM startup
message with a few second delay after 'setenv console s' is invoked.

Tohru Nishimura
Information Technology Centre
Nara Insitute of Science and Technology