Mentor v8.6_4 manual Set Net Dominance, Wire Bus Contention Truth Table

Command Dictionary Set Net Dominance

Set Net Dominance

Tools Supported: FastScan and FlexTest

Scope: Setup mode

Usage

SET NEt Dominance Wire And Or

Description

Specifies the fault effect of bus contention on tri-state nets.

The Set Net Dominance command specifies the fault effect of bus contention on tri-state nets. This provides the capability to detect some faults on tri-state driver enable lines when those drivers connect to a tri-state bus. These faults would be ATPG untestable unless the tool can use the Z-state for detection.

When using FastScan, the Wire behavior is the same where any different binary value results in an X-state.

The truth tables for each type of bus contention fault effect are given in Tables 2-6, 2-7, and 2-8. This command does not affect Good machine behavior.

Table 2-6. WIRE Bus Contention Truth Table

	X		0		1	Z
X	X	X		X		X
0	X	0		X		0
1	X	X		1		1
Z	X	0		1		Z

Table 2-7. AND Bus Contention Truth Table

	X	0	1	Z
X	X	0	X	X
0	0	0	0	0
1	X	0	1	1
Z	X	0	1	Z

FastScan and FlexTest Reference Manual, V8.6_4 2-529