Discussion about the Korg PolySix synthesizer

That's great news.   We can help you a lot more easily if you have a scope.

Probe TP4, pin 32 of the MCU.   Connect the scope probe gnd to TP3 or the big gnd wire,
and clip the tip on the ring at TP4.   Set the triggering to Ch 1.   Adjust the trigger level to 
2V and the volts/div to 2 volts, taking into account whether you are using a 10:1 probe.

According to my comment in the code listing, you should see a pulse there every 7 mSec 
or so if the CPU is executing the code correctly.

Also, you never said what you see on the RESETb input to the CPU.

It should be sitting high.  If you set the scope to trigger at 2V and probe that pin, 
the scope should not trigger, if it's in "manual" trigger mode.  If it triggers, then there 
is a glitch on that pin which would not be good.  Then if you switch to "auto" trigger,
you should see a nice >3.5VDC constant level.

Bob
--------------------------------------------
On Mon, 2/8/16, jw_dewdney@yahoo.com [PolySix] <PolySix@yahoogroups.com> wrote:

 Subject: Re: [PolySix] Re: The Post I didn't want to make....
 To: PolySix@yahoogroups.com
 Date: Monday, February 8, 2016, 12:51 PM
 
 
  
 
 
 
   
 
 
     
       
       
       Hi Bob... actually i realized about five minutes
 after posting that was the thermistor, though i missed it
 because i was working rather slavishly from Jed's
 spreadsheet which didnt seem to have it on
 there. 
 i DO have a
 scope actually. a lovely Tek 2445A. however I'm a bit
 intimidated about troubleshooting logic circuits and
 signals....ive only ever used it for analogue audio stuff
 really... so theres more to learn for me.
 And i DID get some more functioning
 5v test points on the board though still not TP1 which is
 zero... and TP2 is a bit low at 4.1v or thereabouts. I am a
 bit confused as the manual uses a totally different language
 like 'TP-J7' and i am not sure how they correspond
 to the board ... 
 
     
      
 
     
     
 
 
 
 #yiv1538245622 #yiv1538245622 --