Ti’ = ∑ (PS .external input conditions for Hold 0) + ∑ (PS .external input conditions for hold 1)
for i = 1,2,3,...Note: This method solves for the 0’s of the function and it is equivalent to the first method. Example - T Excitation-Input Equations from an ASM Chart
Obtain the excitation equations for the one-hot encoded synchronous Moore-type state machine
from the following ASM Chart.
State Y1Y2 (S0=10 and S1=01 are used and all others are unreachable)
Input X1 X2 X3
Output Z By observing all the sets (Y1 =0 Y1 +=1) and all clears (Y1 =1 Y1 +=0), we can write
the T1 excitation equation, from the state diagram:T1 = Y2.X3 + Y1.(X1.X2.X3’) Repeat the previous step for T2 using Y2 transitions
By observing all the sets (Y2 =0 Y2 +=1) and all clears (Y2 =1 Y2 +=0), we can write
the T2 excitation equation, from the state diagram:T2 = Y2.X3 + Y1.(X1.X2.X3’)Note that T1 and T2 were the same. This is not the norm, and just occurred for this machine. Based on the ASM Chart , this is a Moore machine because the output depends only on the
state variables (flip-flop output)
Z = Y2 Set – Clear method for obtaining J-K Excitation-Input Equations
The following table will be used to write the JK excitation equations directly from state diagram,
ASM chart, or a timing diagram.