This project is based on Digital VLSI Testing and Testability. The netlist is given as input, the code performs SCOAP Controllability and Observability of circuit.
- Create a netlist by naming all wires with numbers (increasing order 1,2,3,.....), starting from input to output. example is shown below
- Save the netlist in .txt format and edit netlist file name in code. (Don't give extra spacing at end of netlist).
NAND 5 3 4
AND 14 6 7
AND 15 8 9
AND 16 10 11
AND 17 12 13
OR 21 14 15
OR 23 16 17
NAND 24 19 20
AND 25 21 24
AND 26 22 23
OR 27 25 26
INPUT 1 7 9 11 13 18
OUTPUT 27
FANOUT 1 2 8 12
FANOUT 2 3 4
FANOUT 5 6 10
FANOUT 18 19 20 22
The code contain many variable and functions which are used in fault collapsing and fault simulation. Each cell in code contain description of variabels and function.
Controllability means difficulty of setting internal circuit lines to 0 or 1 by setting primary circuit inputs.
SCOAP Controllability In above figure CC1_5 means Combinational Controllability of 1 at node 5. And CC0_5 means Combinational Controllability of 0 at node 5.
Observability means difficulty of observing internal circuit lines by observing primary outputs.
SCOAP Observability In above figure CO_5 means Combinational Observability of node 5. And CO_2 means Combinational Observability of node 2.
In above figure at node 10 the values are (3,2) 13.
The values inside brackets represent Combinational Controllability. Here 3 is Combinational Controllability of 0 at node 10, similarly 2 is Combinational Controllability of 1 at node 10. 13 represents Combinational Observability of node 10
Dr. Rathnamala Rao, Assistant Professor, NITK Surathkal