DEC_CC4, 8, 16
4-, 8-, 16-Bit Active Low Decoders
XC3000
| XC4000E
| XC4000X
| XC5200
| XC9000
| Spartan
| SpartanXL
| Virtex
|
|---|
N/A
| N/A
| N/A
| Macro
| N/A
| N/A
| N/A
| Macro
|
These decoders are used to build wide-decoder functions. They are implemented by cascading CY_MUX elements driven by lookup tables (LUTs). The C_IN pin can only be driven by a CY_INIT or by the output (O) of a previous decode stage. When one or more of the inputs (A) are Low, the output is Low. When all the inputs are High and the C_IN input is High, the output is High. You can decode patterns by adding inverters to inputs.
Inputs
| Outputs
|
|---|
A0
| A1
| …
| Az
| C_IN
| O
|
|---|
1
| 1
| 1
| 1
| 1
| 1
|
X
| X
| X
| X
| 0
| 0
|
0
| X
| X
| X
| X
| 0
|
X
| 0
| X
| X
| X
| 0
|
X
| X
| X
| 0
| X
| 0
|
z = 3 for DEC_CC4; z = 7 for DECC_CC8; z = 15 for DECC_CC16
|
