Delta Electronics AH500, Руководство пользователя

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A H 5 0 0 M o t i o n C o n t r o l M o d u l e M a n u a l
5 - 3 8
API Instruction code Operand Function
21 D SUB P S
1
, S
2
, D Binary subtraction
Device X Y M S K 16# F KnM KnS D W T C V Z
S
1
         
S
2
         
D
       
Pulse instruction 16-bit instruction (7 steps) 32-bit instruction (9 steps)
  
E xp la nat io n

The binary value in S
2
is subtracted from the binary value in S
1
, and the
difference is stored in D .

S
1
: Minuend; S
2
: Subtrahend; D : Difference

The highest bit in S
1
and the highest bit in S
2
are sign bits. If the sign bit
in a register is 0, the value in the register is a positive value. If the sign
bit in a register is 1, the value in the register is a negative value.

SM1064 is the zero flag in an Ox motion subroutine, and SM968 is the
zero flag in O100.

SM1065 is the borrow flag in an Ox motion subroutine, and SM969 is the
borrow flag in O100.

SM1066 is the carry flag in an Ox motion subroutine, and SM970 is the
carry flag in O100.

The flags related to 16-bit binary subtraction and 32-bit binary
subtraction are listed below.
16-bit binary subtraction:
1. If the operation result gotten is 0, a zero flag will be ON.
2. If the operation result gotten is less than –32,768, a borrow flag will
be ON.
3. If the operation result gotten is greater than 32,767, a carry flag will
be ON.
32-bit binary subtraction:
1. If the operation result gotten is 0, a zero flag will be ON.
2. If the operation result gotten is less than –2,147,483,648, a borrow
flag will be ON.
3. If the operation result gotten is greater than 2,147,483,647, a carry
flag will be ON.

Please refer to the additional remark on the instruction ADD for more
information about the relations between flags and values.
E xamp le 1

16-bit binary subtraction: When X0.0 is ON, the subtrahend in D10 is
subtracted from the minuend in D0, and the difference is stored in D20.
X0.0
S UB D 0 D 10 D 20
E xamp le 2

When X0.1 is ON, the subtrahend in (D41, D40) is subtracted from the
minuend in (D31, D30), and the difference is stored in (D51, D50).
X0.1
D SU B D 30 D 40 D 50