Variable Precision DSP Blocks User Guide: Agilex™ 5 FPGAs and SoCs

ID 813968
Date 9/20/2024
Public
Document Table of Contents

5.5.2. Input Cascade Tab

Table 52.  Input Cascade Tab
Parameter IP Generated Parameter Value Default Value Description
Enable input cascade for 'ay' input ay_use_scan_in

No

Yes

No

Select to enable input cascade feature for first multiplier.

When you enable input cascade, the multiplier uses scanin port instead of ay input bus as input data.

Only available for the following operation modes:
  • m18×18_full
  • m18×18_sumof2
  • m18×18_systolic
  • m27×27
Enable input cascade for 'by' input by_use_scan_in

No

Yes

No

Select to enable input cascade feature for second multiplier.

When you enable input cascade, the multiplier uses ay input bus instead of by input bus as input data.

Only available for the following operation modes:
  • m18×18_full
  • m18×18_sumof2
  • m18×18_systolic
Enable 'disable_scanin' disable_scanin

No

Yes

No

Select to enable disable_scanin port.

The disable_scanin port is an input signal that can be used dynamically to disable the input cascade feature for top multiplier by disabling the scanin input port.

Only available for the following operation modes:
  • m18×18_full
  • m18×18_sumof2
  • m18×18_systolic

For more information about enabling and disabling scanin port dynamically, refer to the related information.

Scanout
Enable data ay delay register delay_scan_out_ay

No

Yes

No

Select to enable delay register between ay and by input data.

Enable data by delay register delay_scan_out_by

No

Yes

No

Select to enable delay register between by and scanout input data.

Enable 'scanout' port enable_scanout

No

Yes

No

Select to enable scanout port.

The scanout port is an output data bus of the input cascade module.

Only available for the following operation modes:
  • m18×18_full
  • m18×18_sumof2
  • m18×18_systolic
  • m27×27
'scanout' output bus width scan_out_width 0–27 18 Specify the width of scanout output bus.
Only available for the following operation modes:
  • m18×18_full
  • m18×18_sumof2
  • m18×18_systolic
  • m27×27