Altera Floating-Point User Manual
Page 59
Table 6-4: Summary of Input Values and Corresponding Outputs
This table lists the inputs and corresponding outputs obtained from the simulation in the waveform.
Time
Event
0 ns, start-up
dataa[]
value: 0000 0000h
datab[]
value: 0000 0000h
Output value: The undefined value is seen on the
result[]
port, which is ignored.
All values seen on the output port before the 6th clock cycle are merely due to the
behavior of the system during start-up and should be disregarded.
17600 ns
Output value: 7FC0 0000h
Exception handling ports:
nan
asserts
The division of zeros result in a NaN.
2000 ns
dataa[]
value: 2D0B 496Ah
datab[]
value: 3A5A FC26h
Both inputs hold normal values.
20800 ns
Output result: 321F 6EC6h
Exception output ports:
nan
deasserts
The division of two normal value results in a normal value.
11000 ns
dataa[]
value: 046E 78BCh
datab[]
value: 6798 698Bh
Both inputs hold normal values.
27200 ns
Output value: 0h
Exception handling ports:
underflow
and
zero
asserts
The division of the two normal values results in a denormal value. As denormal
values are not supported, the result is zero and the
underflow
port asserts. The
zero
port is also asserted to indicate that the result is zero.
2600 ns
dataa[]
value: 0D72 54A8h
datab[]
value: 0070 0000h
The input port
dataa[]
holds a normal value while the input port
datab[]
holds a
denormal value.
36800 ns
Output value: 7F80 0000h
Exception handling ports:
division_by_zero
asserts
Denormal numbers are forced-zero values, therefore, attempts to divide a normal
value with a zero result in an infinity value.
UG-01058
2014.12.19
ALTFP_DIV Design Example: Understanding the Simulation Results
6-5
ALTFP_DIV IP Core
Altera Corporation