Truth Table/Functionality

Some of the input and output ports of the lpm_bustri function are optional. The following three configurations are valid:

Only the input ports data[LPM_WIDTH-1..0] and enabledt are present, and only the output ports tridata[LPM_WIDTH-1..0] are present. This configuration has the following function:

Inputs

Outputs

enabledt

tridata[LPM_WIDTH-1..0]

0

Z

1

DATA[LPM_WIDTH-1..0]

Inputs	Outputs
0	Z
1	`DATA[LPM_WIDTH-1..0]`

Only the input ports tridata[LPM_WIDTH-1..0] and enabletr are present, and only the output ports result[LPM_WIDTH-1..0] are present. This configuration has the following function:

Inputs	Outputs
`enabletr`	`result[LPM_WIDTH-1..0]`
0	Z
1	`tridata[LPM_WIDTH-1..0]`

All ports are present: input ports data[LPM_WIDTH-1..0], enabledt, and enabletr; output ports result[LPM_WIDTH-1..0]; and bidirectional ports tridata[LPM_WIDTH-1..0]. This configuration has the following function:

Input		Bidirectional	Output
`enabledt`	`enabletr`	`tridata[LPM_WIDTH-1..0]`	`result[LPM_WIDTH-`1`.`.0`]`
0	0	Z (input)	Z
0	1	Z (input)	`tridata[LPM_WIDTH-1..0]`
1	0	`data[LPM_WIDTH-1..0]`	Z
1	1	`data[LPM_WIDTH-1..0]`	`data[LPM_WIDTH-1..0]`