Technical data

DED The value in ACCU 1 (bits 0 to 31) is interpreted as a BCD number.
After the conversion, ACCU 1 contains a 32-bit fixed point number.
DUD The value in ACCU 1 (bits 0 to 31) is interpreted as a 32-bit fixed
point number. After the conversion, ACCU 1 contains a BCD number.
31 30 0
S2
30
. . . . . . . . . 2
0
DUD ↓ DED ↑
31
0
S S S S 10
6
10
5
10
4
10
3
10
2
10
1
10
0
S (sign): 0 = positive
1 = negative
FDG The value in ACCU 1 (bits 0 to 31) is interpreted as a 32-bit fixed
point number. After the conversion, ACCU 1 contains a floating point
number (exponent and mantissa).
GFD The value in ACCU 1 (bits 0 to 31) is interpreted as a floating point
number. After the conversion, ACCU 1 contains a 32-bit fixed point
number.
31 30 0
S2
30
. . . . . . . . . 2
0
FDG ↓
GFD ↑
31 30 ... ... 24 23
0
S2
6
. . . . . . . . . . . . . . 2
0
S2
-1
. . . . . . . . . . 2
-23
Exponent Mantissa
The conversion is made by multiplying the (binary) mantissa by the value
of the (binary) exponent by shifting the mantissa value to more
significant bits past an imaginary decimal point by the value of the
exponent (base 2). After the multiplication, remnants of the original
mantissa remain to the right of the imaginary decimal point. These bit
places are cut off from the whole result.
3
Executive Operations
CPU 928B Programming Guide
C79000-B8576-C898-01
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