The document describes the concept of Algorithmic State Machines (ASM), which are sequential networks that control digital systems executing algorithms. It explains the structure of ASM charts, including different types of machines (Mealy and Moore) and their representation through state and decision boxes. Additionally, it outlines the advantages of ASM charts for understanding and visualizing sequential problems in both combinational and sequential circuits.

1. ALGORITHMIC STATE
MACHINE
1
RAVITESH MISHRA
ASSISTANT PROFESSOR
BCE,MANDIDEEP
Algorithmic State Machine 4/3/2013

2. Algorithmic State Machine (ASM)
2
It is a sequential network which controls a
digital system that carries out a step-by-step
procedure or algorithm.
Algorithmic State Machine 4/3/2013

3. 3
1.State Box :
Contains output list.
2. Decision Box :
Condition is placed.
3. Conditional Output
Box : Contains
conditional output list.
4. ASM Block : contains
one or more exit paths.
Describes machine
operation
Algorithmic State Machine 4/3/2013

4. ASM chart for combinational circuits
4
Contains only one state box Put each term in condition box
For Z=A+BC If A=1,Z=1
Put (A+BC) in one decision box & Z If A=0 (B=0,Z=0 or
in one Conditional output box B=1,C=0/1,z=0/1)
Algorithmic State Machine 4/3/2013

5. 5
ASM chart in
equivalent
form
The other equivalent
charts for Z=A+BC are
Algorithmic State Machine 4/3/2013

6. Development of ASM chart from
state graph
6
There are two types of machines
1. MEALY MACHINE 2. MOORE MACHINE
1. MAELY MACHINE: Output is function of both input & present state
Steps for making ASM chart
i) Represent state by state boxes.
ii) After each box put input in each box.
iii) Depending on values of output the output in conditional box in
paths where it will be “1”.
iv) Depanding on values of input connect the path to next state box.
Algorithmic State Machine 4/3/2013

7. Example of development of ASM chart from Mealy Machine
Consider the Mealy state graph of 111 detector.
7
Algorithmic State Machine 4/3/2013

8. 8
2. MOORE MACHINE :
Output depends on present
state
Steps
1. For each state draw
stae box ,put output in
state box if it is „1‟.
2. Put input in decision
box after each state box.
3. Connect next state
link by inspecting state
graph.
Example: Consider 111
sequence detector.
Algorithmic State Machine 4/3/2013

9. Advantages of ASM chart
9
 Easy to understand.
 May have one or more equivalent forms.
 Can describe both combinational & sequential
circuits.
 Have structured approach to visualise a sequential
problem.
Algorithmic State Machine 4/3/2013