Installing from cdrom not working

[Martin Alejandro Paredes Sanchez]

Hi:

I have a SunFire V100 and V120

I connect a laptop with hyperterminal configured as vt100, I send Ctrl+Break 
and get the prompt "ok"

the terminal emulation works fine

I put the command "boot cdrom" but i only get garbage after booting from 
CD-ROM, I see lines in a stair effect, something like:

D#3P6!
      D#3P6!
            D#3P6!

The lines not always had the same characters (like the example above)

I am using the ISO from the 7.1 RELEASE, burned in a CD-RW

any tip how I can install FreeBSD in the SunFire V100 and V120.

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