Altera Integer Arithmetic IP User Manual
Page 81
Figure 7-4: Multiplication with Coefficient of 3
The following sequence corresponds with the numbered items in the figure:
1. At 190 ns, the sload_coeff signal asserts to register a new coefficient value of 3. The sload_data signal
asserts and triggers a new multiplication. The latest value of the coefficient loaded into the memory is
12. Multiplication occurs between the data_in value of 19 and a coefficient of 12. At the same time, at
190 ns, the sload_coeff signal asserts and triggers the programming of coefficient 3. Although the
multiplication result of 228 at 310 ns is valid, the result_valid signal does not pull high.
2. At 300 ns, the sload_data signal asserts and triggers a new multiplication. However, at 350 ns (less than
four clock cycles after 300 ns), the sload_data signal pulls high again and cancels the previous multipli‐
cation process.
3. Multiplication finally occurs between the data_in value of 35 and a coefficient of 3 at 350 ns.The valid
result, 105, of the computation is displayed at 470 ns.
Note: Altera recommends that you do not assert both the sload_coeff and sload_data signals at the
same time to prevent the programming and computation processes from occurring simultane‐
ously.
7-8
Understanding the Simulation Results
UG-01063
2014.12.19
Altera Corporation
ALTMEMMULT (Memory-based Constant Coefficient Multiplier)