In SX Microcontrollers, SX/B Compiler and SX-Key Tool, metron9 wrote:

The SX may be powering up faster than the intel chip, you may want to leave in a 100ms pause or more to make sure its powered up.  

But even if it isnt the initialize code has no effect on the loop it would just leave the pins in an unknown state and the loop would run normal. 

The HIGH A1_8255 is the SX initializes pin so unless it was set to low somewhere else that would not be the problem.

50mhz is pushing the limits of a breadboard though, depending on the type of breadboard and atmospheric conditions you could have too high capacitance that holds a line high for too long at high speeds, or creates noise similar to a pushbutton switch toggeling the line, without a scope you cant be sure what's going on in that time frame.

Glad it is working. Now i need a new harder problem to solve.

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