Delta Electronics AH500, Руководство пользователя

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C h a p t e r 5 A p p l i e d I n s t r u c t i o n s
5 - 5 9
API Instruction code Operand Function
41 DECO P S, D, n Decoder
Device X Y M S K 16# F KnM KnS D W T C V Z
S
         
D
        
n
 
Pulse instruction 16-bit instruction (7 steps) 32-bit instruction
 
–
E xp la nat io n

The low n bits in S are decoded as the low 2
n
bits in D .

S : Source device; D : Device in which a decoding result is stored n :
Number of bits which are decoded

Generally, the pulse instruction DECOP is used.

D is in the range of 1 to 8.
E xamp le 1

If n is 8, the maximum number of bits which can be decoded is 2
8
=256.

When D is a bit device, n is in the range of 1 to 8. If n is 0, or greater
than 8, an error will occur.

When X2.0 is turned from OFF to ON, the instruction DECOP decodes
X0.0~X0.2 as M100~M107.

If the value in S is 3, M103 will be ON.

After the instruciton is executed, X2.0 will be OFF, and the states of
M100~M107 will remain unchanged.
DECOP X0.0 K3 M100
X2.0
X0.2 X0.1 X0.0
M107 M106 M105 M104 M103 M102 M101 M100
0 1 1
1
0 0 0 0 0 0 0
3 7 6 5 4 2 1 0
4 1 2
3
E xamp le 2

If n is 8, the maximum number of bits which can be decoded is 2
8
=256.

When S is a word device, n is in the range of 1 to 8. If n is 0, or greater
than 8, an error will occur.

When X2.0 is turned from OFF to ON, the instruction DECOP decodes
b2~b0 in D10 as b7~b0 in D20, and b15~b8 in D10 become 0.

The low 3 bits in D10 are decoded as the low 8 bits in D20. The high 8
bits in D20 are 0.

After the instruciton is executed, X2.0 will be OFF, and the value in D20
remain unchanged.
DECOP D10 K3 D20
X2.0
0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1
4 2 1
3
b15 b0
Bit 15~ bi t 8
in D10 bec ome 0.
b15 b0
D 10
D 20
7 6 5 4 2 1 0