[HN Gopher] Testing the Z80 Chip with a 1970s Beauty
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       Testing the Z80 Chip with a 1970s Beauty
        
       Author : trakfactri
       Score  : 51 points
       Date   : 2024-11-11 20:11 UTC (2 hours ago)
        
 (HTM) web link (mtsi.substack.com)
 (TXT) w3m dump (mtsi.substack.com)
        
       | wrs wrote:
       | Does anyone know what the tester for a 12-core 3 GHz processor
       | looks like now?
        
         | alain94040 wrote:
         | Don't know what the latest is, but this from Teradyne was
         | probably close:
         | https://www.teradyne.com/products/ultraflexplus/
        
         | femto wrote:
         | Potentially the processor has Built-In-Self-Test (BIST)?
         | Connect up the JTAG bus, send the right commands and the chip
         | tells you that it is okay.
        
       | jandrese wrote:
       | > We had to be careful about those AC utility jacks. The tester
       | ground was at -11 volts at several hundred amps. If you clipped a
       | scope to a ground, it would happily melt the insulation off the
       | scope probe until it stunk up the room and pooled on the floor.
       | We had to use a three-prong adapter with the ground cut off.
       | 
       | You don't get this kind of excitement anymore with modern
       | electronics.
        
         | fortran77 wrote:
         | I have the same issue today when I fix old tube radios. Once
         | side of the mains is connected to chassis -- and there are no
         | polarized plugs. I use an isolation transformer, otherwise if I
         | try to use a scope, I'd blow it out immediately--50% of the
         | time.
        
           | Aloha wrote:
           | I am cheap.
           | 
           | So I've never used an isolation transformer, I measure from
           | test equipment chassis to chassis and check voltage
           | potential, then roll the plug as needed.
        
       | nutrie wrote:
       | Damn! I was expecting old porn.
        
       | PaulHoule wrote:
       | First thing I made with Arduino was a tester for (much less
       | complex) 54xx and 74xx chips.
        
       | femto wrote:
       | Typo? "ZIP DIP socket" should be "ZIF DIP socket", as in Zero
       | Insertion Force?
        
         | Affric wrote:
         | Surely autocorrect.
        
       | UncleOxidant wrote:
       | I worked at Fairchild Sentry DTS in San Jose (at that time very
       | close to the airport) circa 1984-1986 on the series 50 ATE. It
       | was a beast. At the time it could clock & test up to 50MHz (hence
       | the '50'). It was pretty much all ECL which would get very hot.
       | Each unit shipped with a DEC VAX - that was my intro to VMS which
       | had some interesting features like file versioning. I worked as a
       | tech on the production floor building the 50. It was just being
       | introduced and there were so many problems with getting them up
       | and running. The systems had to be calibrated and that was done
       | by changing the lengths of hundreds of delay wires on the
       | backplane. No two systems were exactly the same because of this
       | (I'm sure this was also an issue with earlier ATE models as
       | well). IIRC the 50 was "introduced" (announced) in '84 shortly
       | before the time I started. I recall that we were way behind in
       | producing them and there was lots of blame flying between
       | production (us) and engineering - as in maybe they designed
       | something that wasn't easily reproducible.
       | 
       | In my next job I moved into an engineering role and I always kept
       | that experience as a technician in the back of my mind: make sure
       | what you're designing can be built with reproducible results.
        
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       (page generated 2024-11-11 23:00 UTC)