FX Series Programmable Controlers Applied Instructions 5
5-44
5.5.3 ENCO (FNC 42)
Operation:
The hi
hest active bit within the readable ran
e has
its location noted as a numbered offset from the
source head address (S). This is stored in the
destination re
ister (D).
Points to note:
a) The readable ran
e is defined b
the lar
est number storable in a binar
format within the
number of destination stora
e bits specified b
n, i.e. if n was equal to 4 bits a maximum
number within the ran
e 0 to 15 can be written to the destination device. Hence, if bit
devices were bein
used as the source data, 16 bit devices would be used, i.e. the head bit
device and 15 further, consecutive devices.
b) If the stored destination number is 0 (zero) then the source head address bit is ON, i.e. the
active bit has a 0 (zero) offset from the head address. However, if NO bits are ON within the
source area, 0 (zero) is written to the destination device and an error is
enerated.
c) When the source device is a data or word device n must be taken from the ran
e 1
to 4 as
there are only 16 source bits available within a single data word.
Mnemonic Function
Operands
Program steps
SD n
ENCO
FNC 42
(Encode)
Then location of
the hi
hest active
bit is stored as a
numerical position
from the head
address
X, Y, M, S,
T, C, D, V,
Z
T, C, D, V,
Z
K, H,
Note:
S=X, Y, M, S then
n ran
e=1-8
S= T,C,D then
n ran
e = 1-4
n = 0, then no
processin
ENCO,
ENCOP:
7 steps
X5
D 10 K 3
[ S ] [ D ]
M 10
[ n ]
ENCO
M15 M14 M13 M12 M11 M10M16M17
01000 000
7. 6. 5. 4. 3. 2. 1. 0.
0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1
D10
421
..
+
= 3
