I've been intending to do some Intellivision tinkering for literally years.  Finally got one of mine open and put it on the logic analyzer here at work and immediately (we're talking first cycles) notice what I can't explain after looking at the cycles.  The first instruction fetched has opcode 0x4.  Easy enough to decode, that's a jump.  According to all the references I checked (Intelliwiki, CP1610 datasheet, jzintv implementation) a jump is 12 cycles.  If so, why do I count 13? :-)

I've looked at several 0x4 cycles and they all appear to be 13 cycles by my reckoning.  I've not spent much time on this, but some other decodes seem one NACT cycle larger than I would expect as well, but not all.  

I've placed a screenshot at
http://farm4.static.flickr.com/3533/3799959330_d94007a12f_o.jpg 

I'm probably just counting wrong, or missing something basic, but my curiosity got the better of me and I'm hoping someone can explain what I'm seeing.  I've marked off what I believe to be the boundaries of the instruction.

Travis