>> On a Sun 3/150 system I have copied the miniroot into the swap partition b
>> (sd0b) using tape, when I halt the system and enter the command >b sd(0,0,1)
>> -s at the boot prom command line I get back:
>> 
>> Boot sd(0,0,1)
>> 
>> Exception 0x2C at 0x00004000.
>> 
>> Does anyone know why I am getting the "Exception"?
>
>I was getting the exact same error on a 3/50 a couple years ago.
>Except that time, I was trying to boot SunOS 4.1.1 from a tape.  I
>never figured out what the problem was for sure, but it could have
>been a bad tape, a bad tape drive, or maybe a malfunctioning 3/50.
>
>Maybe the FE's manual has a list of exceptions for the sun 3
>hardware...
>

A quick look at the MC68020 users manual shows:

  vector #    offset     Assignment
  --------    ------     ----------
        11      0x2C     Line 1111 Emulator
  44 (=0x2C)    0xB0     Trap #12 (0xC) Instruction vector

Line 1111 is usually used for co-processor instructions (ie. floating
point. MMU), Trap 12 - who knows.


                                               Dean