Altera Floating-Point - Manual (Page 122)

Table 17-5: Summary of Input Values and Corresponding Outputs
Time Event
0 ns, start-up
dataa[]
value: C394 AD22 761B 9EE5h
Output value: The
result[]
port displays 0 regardless of what the input
value is. This value seen on the output port before the 6th clock cycle is
merely due to the behavior of the system during start-up and should be
disregarded.
55 ns Output value: FAD4 B762 7918 46C0h
150 ns
dataa[]
value: 000F 0000 5555 1111h
This value is a denormal number.
205 ns Denormal inputs are not supported and are forced to zero before conversion
takes place.
300 ns
dataa[]
value: 5706 40CF OEC6 1176h
355 ns Output value: 7FFF FFFF FFFF FFFFh
Exception handling ports:
overflow
asserts.
The
overflow
flag is triggered because the width of the resulting integer is
more than the maximum width allowed, and the value seen on the
result[]
port is the standard value used to represent a positive overflow number.
350 ns
dataa[]
value: C728 3147 8444 1F75h
405 ns Output value: 8000 0000 0000 0000h
Exception handling ports:
overflow
remains asserted.
This is a standard value to represent a negative overflow number.
400 ns
dataa[]
value: 145A 257C 895A B309h
455 ns Output value: 0000 0000h
Exception handling ports:
underflow
asserts.
The input value triggers the
underflow
port because the exponent of the
input value is less than the exponent bias of 1023.
500 ns
dataa[]
value: FFFF 0000 DDDD 5555h
This value is a NaN.
555 ns Output value: 0000 0000h
Exception handling ports:
nan
asserts.
UG-01058
2014.12.19
ALTFP_CONVERT Design Example: Understanding the Simulation Results 17-7
ALTFP_CONVERT IP Core Altera Corporation
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