Altera RAM-Based Shift Register - Manual (Page 23)

Chapter 3: Specifications 3–3
Ports and Parameters for the ALTSHIFT_TAPS Megafunction
May 2013 Altera Corporation RAM-Based Shift Register (ALTSHIFT_TAPS) Megafunction User Guide
Table 3–3 shows the ALTSHIFT_TAPS megafunction parameters.
Table 3–3. Shift Register (RAM-based) MegaWizard Plug_In Parameters
Name Type Required Description
NUMBER_OF_TAPS Integer Yes Specifies the number of regularly spaced taps along the shift register.
TAP_DISTANCE Integer Yes
Specifies the distance between the regularly spaced taps in clock cycles.
This number translates to the number of RAM words that will be used.
TAP_DISTANCE
must be at least 3.
WIDTH Integer Yes Specifies the width of the input pattern.
POWER_UP_STATE String No
Specifies the shift register contents at power-up. Values are CLEARED and
DONT_CARE
. If omitted, the default is CLEARED.
Value Description
CLEARED
Zero content. For Stratix and
Stratix II device families, you must
use M512 or M4K RAM blocks.
DONT_CARE
Unknown contents. M-RAM blocks
can be used with this setting.