Input Register Bank
The input register bank consists of data, dynamic control signals, and two sets of delay registers.
All the registers in the DSP blocks are positive-edge triggered and cleared on power up. Each multiplier
operand can feed an input register or a multiplier directly, bypassing the input registers.
The following variable precision DSP block signals control the input registers within the variable precision
DSP block:
•
CLK[2..0]
•
ENA[2..0]
•
ACLR[0]
In 18 x 19 mode, you can use the delay registers to balance the latency requirements when you use both the
input cascade and chainout features.
The tap-delay line feature allows you to drive the top leg of the multiplier input, dataa_y0 and datab_y1 in
18 x 19 mode and dataa_y0 only in 27 x 27 mode, from the general routing or cascade chain.
Variable Precision DSP Blocks in Cyclone V Devices
Altera Corporation
CV-52003
Input Register Bank
3-6
2014.01.10