Purpose:  To convert a Signed quantity to a different data type. 
Format:  opcode src.rx, dst.wy 
Operation:  dst < converted src; 
Condition Codes: 
N < dst LSS 0;
Z < dst EQL 0;
V < {src cannot be represented in dst};
C < 0; 
Exceptions:  Integer Overflow;
Floating Point Overflow
Reserved Operand (Floating Point) 
Opcodes: 
99  CVTBW  Convert Byte to Word 
98  CVTBL  Convert Byte to Long 
4C  CVTBF  Convert Byte to Float 
6C  CVTBD  Convert Byte to Double 
33  CVTWB  Convert Word to Byte 
32  CVTWL  Convert Word to Long 
4D  CVTWF  Convert Word to Float 
6D  CVTWD  Convert Word to Double 
F6  CVTLB  Convert Long to Byte 
F7  CVTLW  Convert Long to Word 
4E  CVTLF  Convert Long to Float 
6E  CVTLD  Convert Long to Double 
48  CVTFB  Convert Float to Byte 
49  CVTFW  Convert Float to Word 
4A  CVTFL  Convert Float to Long 
4B  CVTRFL  Convert Rounded Float to Long 
56  CVTFD  Convert Float to Double 
68  CVTDB  Convert Double to Byte 
69  CVTDW  Convert Double to Word 
6A  CVTDL  Convert Double to Long 
6B  CVTRDL  Convert Double Rounded to Long 
76  CVTDF  Convert Double to Float 

Description: 
The source operand is convert to the data type of the destination operand and the destination operand is replaced by the result. The source operand is unaffected.
For integer format, conversion of a shorter data type to a longer data type is done by sign extension. A conversion of a longer data type to a shorter data type is done by truncation of the most significant bit.
For floating format, teh conversions are as follows:
CVTBF  exact  CVTFB  truncated 
CVTBD  exact  CVTDB  truncated 
CVTWF  exact  CVTFW  truncated 
CVTWD  exact  CVTDW  truncated 
CVTLF  rounded  CVTFL  truncated 
CVTLD  exact  CVTDL  truncated 
CVTFD  exact  CVTDF  rounded 
CVTRFL  rounded  CVTRDL  rounded 

Notes: 
 1.
 Integer overflow occurs if any trucated bits of the source operand are not equal to the sign bit of the destination operand.
 2.
 Only converts with an integer destination operand can result in an integer overflow. On integer overflow, the destination operand is replaced by the low order bits of the true result.
 3.
 Only CVTDF can result in floating overflow. On floating overflow, the destination operand is replaced by an operand of all 0 bits except for a sign bit of 1 (a reserved operand). N < 1; Z &lf 0; V <1; and C < 0.
 4.
 Only converts with a floating point source operand can result in a reserved operand fault. On a reserved operand fault, the destination operand is unaffected and the condition codes are unpredictable.
