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Need help with a simple GAL programming problem.

Could anybody out there that remembers programming GAL's (specifically the 24 pin 22V10 variety), help me on what I'm sure is a simple problem.
I want the GAL to topple low  to high on a port input. and stay high., The next time on a port input toggle back high to low and stay low. In other words inputting from a port toggles the output. I'm a bit limited with pins available, only 3:-

PIN 1   NC
PIN 2   A0                         ;Note these are actual S100 bus address lines (outside the 80386)
PIN 3   A1
PIN 4   A2
PIN 5   A3
PIN 6   A4
PIN 7   A5
PIN 8   A6
PIN 9   A7
PIN 10  A8
PIN 11  A9
Pin 12  GND
Pin 13  A10
Pin 14  A11
Pin 15  A12
Pin 16  A13
Pin 17  A14
Pin 18  A15        
Pin 19  sINP                            ;S100 bus status Port IN line
Pin 20  pDBIN                         ;S100 bus port read
Pin 21  TOGGLE_OUTPUT             
Pin 22  NC              
Pin 23  NC
;----------------------------------- Boolean Equation Segment ------


TOGGLE_OUTPUT    =      A0 * /A1 * A2 * A3 * /A4 * A5 * A6 * A7                        ;EDH = 1110 1101
                                        * /A8 * /A9 * /A10 * /A11 * /A12 * /A13 * /A14 * /A15
                                        *  sINP * pDBIN                                                                ;Activate board with Z80 monitor QIED command

I'm assuming I need a register output, not sure what the clock should be.  Any suggestions as to a layout.