DEX        DEcrement indeX register
Category:  Index register control
Function:  IX <-- (IX) - 0001

Effects on the Condition Codes
H = N/A
I = N/A
N = N/A
Z = (~RH7&~RH6&...&~RH0)&(~RL7&~RL6&...&~RL0)
V = N/A
C = N/A

ADDR    MNEM    OPER        1st     2nd     3rd
MODE    ONIC    FRMT        BYTE    BYTE    BYTE
________________________________________________

IMPL    DEX                 09