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4.2.8 LPM_DECODE |
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Copyright © 1998 University of Manchester |
| Description | Comments | |||
| Data input. Treated as unsigned binary number. | Vector, LPM_Width wide | |||
| Enable. All outputs low when not active | Default value is Active (High) if absent. | |||
| For i = 0 to LPM_Decodes
if (i = Data) Eqi = 1 else Eqi = 0 | Vector, LPM_Decodes wide.
If Data > = LPM_Decodes then all Eqi are 0 | |||
| Clock for pipelined usage | Note 1 | |||
| Asynchronous Clear | Note 2 |
Note 1: The clock port provides for pipelined operation of the LPM_MUX. If a latency other 0 (default value) is specified, then the clock port must be connected.
Note 2: The pipelined initializes to undefined. The Aclr port
may be used at any time to reset the pipeline to all 0's asynchronously
to clock.
| Value | Comments | ||
| LPM Value > 0 | Width of input vector | ||
| 0 < LPM Value < = 2LPM_Width | Number of explicit decodes | ||
| LPM Value > = 0 | Default is 0 - non-pipelined |
| Data vector |
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| Data = LPM_Decodes -1 | ||
| Data = LPM_Decodes | ||
| Data > LPM_Decodes |
Note 1: If Data = i and Eqi is not connected or does not appear in the symbol then all outputs will be low.