DL205 User Manual, 4th Edition, Rev. B
5–96
Chapter 5: Standard RLL Instructions - Math
1
2
3
4
5
6
7
8
9
10
11
12
13
14
A
B
C
D
Multiply Real (MULR)
The Multiply Real instruction multiplies a real number in
the accumulator with either a real constant or a real number
occupying two consecutive V-memory locations. The result
resides in the accumulator. Both numbers must be Real
data type (IEEE floating point format).
NOTE: Status flags are valid only until another instruction uses the same flag.
NOTE: The current HPP does not support real number entry with automatic conversion to the 32-bit IEEE
format. You must use DirectSOFT for this feature.
DirectSOFT
LDR
R7.0
X1
Load the real number 7.0
into the accumulator .
MULR
R 15.0
Multi pl y the accum ul ator
contents by the r eal number
15.0
00000000000000000100001011010010
8421842184218421
8421842184218421
Acc.
42D2 0000
V1400V1401
Real Val ue
Copy the r esult in the accumulator
to V1400 and V1401.
OUTD
V1400
Implies 2 (exp 6)
133 -- 127 = 6
(Hex numb er)
Sign Bit
40E0 0000
000040E0
(MULR)
(Accumulator )
4170 0000X
000042D2
Acc.
7
(decimal)
x15
105
1.101001 x 2 (exp 6) = 1101001. binary= 105 decimal128 + 4 + 1 = 133
Exponent (8 bits)
Mantissa (23 bits)
Discrete Bit Flags Description
SP63 On when the result of the instruction causes the value in the accumulator to be zero.
SP70 On anytime the value in the accumulator is negative.
SP71 On anytime the V-memory specified by a pointer (P) is not valid.
SP72 On anytime the value in the accumulator is an invalid floating point number.
SP73 On when a signed addition or subtraction results in an incorrect sign bit.
SP74 On anytime a floating point math operation results in an underflow error.
SP75 On when a real number instruction is executed and a non-real number was encountered.
Operand Data Type DL250-1 Range DL260 Range
A aaa aaa
V-memory V All. (See page 3-55) All. (See page 3-56)
Pointer P All V-memory (See page 3-55) All V-memory (See page 3-56)
Constant R
-3.402823E+038 to
+ 3.402823E+038
-3.402823E+038 to
+ 3.402823E+038
DS Used
HPP N/A