eht@O.GP.CS.CMU.EDU (Eric Thayer) (09/08/89)
Did you know that there are actually instructions on the 56k which can potentially damage the chip? Things like move x:ea -> b and y:ea -> b. The assembler will not generate insane instructions, but if you go executing random data, there is the possibility of executing one of these. Just thought it might be interesting.
eht@f.word.cs.cmu.edu (Eric Thayer) (09/08/89)
You can find more information on Insane DSP56000 instructions on page A-260 of the Rev 1 User's Manual for the chip. But, it says instructions like <op> x:ea,b y:ea,b Can cause damage to the XDB and YDB bus drivers and permanent damage to the chip could result. So, don't put weird DC directives in your P space. -- Eric H. Thayer School of Computer Science, Carnegie Mellon (412) 268-7679 5000 Forbes Ave, Pittsburgh, PA 15213
MDM107@PSUVM.BITNET (Michael Mellinger) (09/10/89)
In article <6102@pt.cs.cmu.edu>, eht@f.word.cs.cmu.edu (Eric Thayer) says: > >You can find more information on Insane DSP56000 instructions on page A-260 >of the Rev 1 User's Manual for the chip. But, it says instructions like > > <op> x:ea,b y:ea,b > >Can cause damage to the XDB and YDB bus drivers and permanent damage to the >chip could result. So, don't put weird DC directives in your P space. > How long do you think it will take before a nasty virus does this? Mike
shannon@iuvax.cs.indiana.edu (Greg Shannon) (09/10/89)
This discussion that damaging codes can be produced for the DSP are quite concerning to me since my research funds are invested in 2 of these machines so far. I would greatly appreciate it if someone from NeXT would comment on this problem -- is it true or not?? In particular, does the warranty covers DSP chips damaged because of this, yes? Also, what is to keep a bug in .8 or .9 from creating such damage. How does the warranty apply if the DSP chip was damaged before the warranty ran out, but it wasn't discovered for some time? In general, if this possibility of damaging the DSP is true, it seems that all NeXT owners have quite a problem on their hands. (What is to keep a malicious student from killing the DSP?) Again, someone from NeXT should respond to this, soon! Greg Shannon Computer Science Dept Indiana University