Mitsubishi Electric MELSEC FX3U Programming Manual page 663

FX /FX /FX Series Programmable Controllers
3G 3U 3UC
Programming Manual - Basic & Applied Instruction Edition
Explanation of function and operation
1. 16-bit operation (LEFT and LEFTP)
"n" characters are extracted from the left end (that is, from the head) of the character string data stored in
and later and stored to
S
If the number of characters specified by "n" is "0", the NULL code (0000H) is stored to
When characters are extracted from a character string, "00H" is automatically added at the end of the
extracted characters.
- When the number of extracted characters is odd, "00H" is stored in the high-order byte of a device
storing the last character.
- When the number of extracted characters is even, "0000H" is stored in the device after the last
character.
Command
input
FNC205
LEFT
b15----------------------b8b7-----------------------b0
ASCII code for 2nd
S
character
ASCII code for 4th
S +1
character
ASCII code for n-1
character
ASCII code for n+1
character
In the case of "n = 7"
b15----------------------b8b7----------------------b0
S 42H(B)
44H(D)
S +1
S +2 46H(F)
S +3 32H(2)
34H(4)
S +4
S +5
• A character string stored in
"00H" is first detected in byte units.
Cautions
When handling character codes other than ASCII codes, note the following contents:
• The number of characters is handled in byte units (8 bits). Accordingly, in the case of character codes in
which 2 bytes express 1 character such as shift JIS codes, the length of 1 character is detected as "2".
• When extracting characters from a character string including character codes in which 2 bytes express 1
character such as shift JIS codes, consider the number of characters to be extracted in units of character
codes for 1 character.
Note that the expected character code is not given if only 1 byte is executed out of a 2-byte character code.
and later.
D
S
D
ASCII code for 1st
character
ASCII code for 3rd
character
ASCII code for n-2
character
ASCII code for n
character
ASCII code for last
00H
character
41H(A)
43H(C)
45H(E)
31H(1)
33H(3)
00H 35H(5)
"ABCDEF12345"
and later indicates data stored in devices from the specified device until
S
26 Character String Control – FNC200 to FNC209
26.6 FNC205 – LEFT / Extracting Character String Data from the Left
n
b15----------------------b8b7-----------------------b0
D
ASCII code for 2nd
D +1
ASCII code for 4th
ASCII code for n-1
ASCII code for 1st character
b15----------------------b8b7-----------------------b0
D
D +1
D +2
D +3
ASCII code for 7th character
.
D
ASCII code for 1st
character character
ASCII code for 3rd
character character
ASCII code for n-2
character character
ASCII code for n
00H
character
42H(B) 41H(A)
44H(D) 43H(C)
46H(F) 45H(E)
00H 31H(1)
"ABCDEF1"
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