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Basic I/O Unit Instructions Section 3-22
Precautions Do not read or write the system word (D) from any other instruction.
7SEG(214) will not operate correctly if the system word is accessed by
another instruction. The system word is not initialized by 7SEG(214) in the
first cycle when program execution starts. If 7SEG(214) is being used from
the first cycle, clear the system word from the program.
7SEG(214) will not operate correctly if I/O refreshing is not performed with the
Output Unit connected to the 7-segment display after 7SEG(214) is executed.
Consequently, do not connect the external matrix to the following Units.
• Communications Slaves (DeviceNet or CompoBus/S Slaves)
Example In this example, 7SEG(214) converts the 8 digits of BCD data in D100 and
D101 and outputs the data through CIO 102.
There are 8 digits of data being output and the 7-segment display’s logic is the
same as the Output Unit’s logic, so the control data (C) is set to 0004. D32000
is used as the system word, D.
3-22-8 INTELLIGENT I/O READ: IORD(222)
Purpose Reads the contents of memory area of a Special I/O Unit or CPU Bus Unit.
This instruction can be used in the CP1H CPU Units only. It cannot be used in
the CP1L CPU Units. If IORD(222) is used in a CP1L CPU Unit, Error Flag
(ER) will be turned ON.
Ladder Symbol
Variations
Applicable Program Areas
Operands C: Depends on Special I/O Unit or CPU Bus Unit.
S: Special I/O Unit: 0000 to 005F hex
(to specify unit numbers 0 to 95)
CPU Bus Unit: 8000 to 800F hex
(to specify unit numbers 0 to F hex)
S+1: Number of words to transfer
(0001 to 0080 hex, depends on Special I/O Unit or CPU Bus Unit)
S
O
C
D
7SEG(214)
D100
102
004
D32000
P_On
Always ON Flag
IORD(222)
C
S
D
C: Control data
S: Transfer source and number of words
D: Transfer destination
Variations Executed Each Cycle for ON Condition IORD(222)
Executed Once for Upward Differentiation @IORD(222)
Executed Once for Downward Differentiation Not supported.
Immediate Refreshing Specification Not supported.
Block program areas Step program areas Subroutines Interrupt tasks
OK OK OK OK
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