Libraries GuideChapter 5: Design Elements (F5MAP to FTSRLE)
FTCP
Toggle Flip-Flop with Toggle Enable and Asynchronous Clear and Preset
XC3000
| XC4000E
| XC4000X
| XC5200
| XC9000
| Spartan
| SpartanXL
| Spartan2
| Virtex
|
|---|
N/A
| N/A
| N/A
| N/A
| Primitive
| N/A
| N/A
| N/A
| N/A
|
FTCP is a toggle flip-flop with toggle enable and asynchronous clear and preset. When the asynchronous clear (CLR) input is High, all other inputs are ignored and the output (Q) is reset Low. When the asynchronous preset (PRE) input is High, all other inputs are ignored and Q is set High. When the toggle enable input (T) is High and CLR and PRE are Low, output Q toggles, or changes state, during the Low-to-High clock (C) transition.
The flip-flop is asynchronously cleared, output Low, when power is applied. For CPLDs, the power-on condition can be simulated by applying a High-level pulse on the PRLD global net.
Inputs
| Outputs
|
|---|
CLR
| PRE
| T
| C
| Q
|
|---|
1
| 0
| X
| X
| 0
|
0
| 1
| X
| X
| 1
|
0
| 0
| 0
| X
| No Chg
|
0
| 0
| 1
| 
| Toggle
|
