EIT
4.2 EIT Events
4
3) Inexact Exception (IXCT)
The exception occurs when the operation result differs from a result led out with an infinite range of
precision. The following table shows the operation results and the respective conditions in which each
IXCT occurs.
Table 4.2.3 Operation Results when an IXCT Occurred
Operation Result (Content of the Destination Register)
Occurrence Condition
When the IXCT EIT processing for is
masked (Note 1)
When the IXCT EIT processing is
executed (Note 2)
Overflow occurs in OVF masked
condition
Reference OVF operation results
Rounded value
No change
No change
Rounding occurs
Note 1: When the inexact exception enable (EX) bit (FPSR register bit 17) = "0"
Note 2: When the inexact exception enable (EX) bit (FPSR register bit 17) = "1"
4) Zero Division Exception (DIV0)
The exception occurs when a finite nonzero value is divided by zero. The following table shows the
operation results when a DIV0 is occurs.
Table 4.2.4 Operation Results When a DIV0 Occurred
Operation Result (Content of the Destination Register)
Dividend
When the DIV0 EIT processing is masked
(Note 1)
When the DIV0 EIT processing is
executed (Note 2)
+-Infinity (Sign is derived by exclusive
ORing the signs of the divisor and
dividend.)
Nonzero finite value
No change
Note 1: When the zero division exception enable (EZ) bit (FPSR register bit 19) = "0"
Note 2: When the zero division exception enable (EZ) bit (FPSR register bit 19) = "1"
Please note that the DIV0 EIT processing does not occur in the following conditions.
Table 4.2.5 Cases in Which No DIV0 Occur
Dividend
Behavior
An invalid operation exception occurs
No exceptions occur (with the result = Infinity")
0
Infinity
"
32180 Group User’s Manual (Rev.1.0)
4-4
RENESAS [ RENESAS TECHNOLOGY CORP ]
