Omron CS1G/H-CPUxxH Instructions Manual page 857

Basic I/O Unit Instructions
Flags
Precautions
836
Name Label
Error Flag ER
Equals Flag =
When "0001" is designated for the number of words to be transferred (D+1),
the data for S can be designated by a constant. If a constant is designated for
S when the number of words to be transferred is not "0001," an error will occur
and the Error Flag will turn ON.
The Equals Flag will turn ON if the writing operation is completed normally.
The Equals Flag will turn OFF if the writing operation cannot be completed
normally due to the Special I/O Unit being busy.
Whenever any of the following occur, an error will occur and the Error Flag will
turn ON.
• There is an I/O Unit verification error, a Special I/O Unit setting error, or a
Special I/O Unit error at the Special I/O Unit.
• The number of words to transfer (D) is outside the range of 0001 to 0080
(hex).
• The unit number (D) is outside the range of 0000 to 005F.
• The designated Special I/O Unit is on SYSMAC BUS.
• A Special I/O Unit not affected by IOWR(223) is designated.
• A Special I/O Unit with a Special I/O Unit setting error or a Special I/O
Unit error is designated.
When IOWR(223) is executed, the execution results are reflected in the condi-
tion flags. In particular, the Equals Flag turns ON when reading is completed.
Input the condition flags such as the Equals Flag with output branching from
the same input conditions as the IOWR(223) instruction.
If the Special I/O Unit is busy, the writing operation will not be executed. Use
the Equals Flag to create a self-maintaining program, as shown below, so that
IOWR(223) will be executed with each cycle until the writing operation is exe-
cuted.
Operation
ON if the number of words to transfer (D) is outside the
range of 0001 to 0080 hex.
ON if the unit number (D) is outside the range of 0000 to
005F hex.
ON if S is designated by a constant when the number of
words to be transferred (D+1) is not 0001 hex.
ON if the designated Special I/O Unit is on SYSMAC
BUS.
ON if a Special I/O Unit not affected by IOWR(223) is des-
ignated.
ON if a Special I/O Unit with a Special I/O Unit setting
error or a Special I/O Unit error is designated.
With the CS1D CPU Units: ON if the active and standby
CPU Units could not be synchronized.
OFF in all other cases.
ON if writing operation is completed normally.
OFF if writing operation is not completed normally.
Section 3-23