Arria® V Device Handbook: Volume 1: Device Interfaces and Integration

ID 683213
Date 10/18/2023
Public
Document Table of Contents

3.5.1. 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 18 and 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 inputs from general routing or from the cascade chain. The following inputs can be driven from either the general routing or from the cascade chain:

  • For Arria® V GX, GT, SX, and ST devices:
    • dataa_y0 and datab_y1 in 18 x 19 mode
    • dataa_y0 in 27 x 27 mode
  • For Arria® V GZ devices:
    • dataa_y0[17..0] and datab_y1[17..0] in 18 x 18 mode
    • dataa_y0 in 27 x 27 mode

The Arria® V GZ variable precision DSP block support 18-bit and 27-bit input cascading.

These figures show the input registers for Arria® V devices.

Figure 28. Input Register of a Variable Precision DSP Block in 18 x 19 Mode for Arria V GX, GT, SX, and ST DevicesThe figures show the data registers only. Registers for the control signals are not shown.


Figure 29. Input Register of a Variable Precision DSP Block in 27 x 27 Mode for Arria V GX, GT, SX, and ST DevicesThe figures show the data registers only. Registers for the control signals are not shown.


Figure 30. Input Register of a Variable Precision DSP Block in 18 x 18 Mode for Arria® V GZ DevicesThe figures show the data registers only. Registers for the control signals are not shown.


Figure 31. Input Register of a Variable Precision DSP Block in 27 x 27 Mode for Arria® V GZ DevicesThe figures show the data registers only. Registers for the control signals are not shown.