Well Michael, I finely got around to testing your State_Machine tutorial. Great Job.

I made up the LED block and switches per your schematic. Actually I usally have such a set for 'first' testing of hardware. This time I tested with my Cygnal C8052F124-TB assembly and handled the software as follows:
-Made a file folder to hold the project.
-Used the Cygnal Configuration Wizzard to configure my hardware. This file I saved as Project.inc
-Then I copied your code into a file called Project.asm
-Opened new project in the Cygnal IDE called Project
-Brought in Project.asm (your code.asm)and modified it by commenting out the $INCLUDE(REG51FX.INC)because I am using the Cygnal C8051F124 (kit board)
-Assembled and got an error. The uC I am using has 2 serial ports and therefore the Interrupt vector is ES0 (as opposed to just ES).
-Made the correction, reassembled, linked, downloaded, and started a real learning session with the Cygnal IDE Debugger. Lots of fun. For the skeptics all the rest of Michaels program was without a flaw.
-Note to newbes--Get this code, study EVERY instruction and structure, you will go to bed with a good feeling because there is lots to learn here.
TomB