24
Word(s)
Function
Bit(s)
253
00 to 07
FAL number output area.
08
Low Battery Flag
09
Cycle Time Error Flag
10
I/O Verification Error Flag
11
Rack-mounting Host Link Unit Level 0 Error Flag
12
Remote I/O Error Flag
13
Normally ON Flag
14
Normally OFF Flag
15
First Cycle
254
00
1-minute clock pulse bit
01
0.02-second clock pulse bit
02 to 06
Reserved for function expansion. Do not use.
07
Step Flag
08 to 12
Duplex System flags
13 to 15
Reserved for function expansion. Do not use.
255
00
0.1-second clock pulse bit
01
0.2-second clock pulse bit
02
1.0-second clock pulse bit
03
Instruction Execution Error (ER) Flag
04
Carry (CY) Flag
05
Greater Than (GR) Flag
06
Equals (EQ) Flag
07
Less Than (LE) Flag
3-4-1
Link System Flags and Control Bits
Use of the following SR bits depends on the configuration of any Link Sys-
tems to which your PC belongs. These flags and control bits are used when
Link Units, such as PC Link Units, SYSMAC LINK Units, Remote I/O Units,
SYSMAC NET Link Units, or Host Link Units, are mounted to the PC Racks
or to the CPU. For additional information, consult the System Manual for the
particular Units involved.
The following bits can be employed as work bits when the PC does not be-
long to the Link System associated with them.
Remote I/O Systems
Word 251 is used to indicate errors in Remote I/O Systems. The function of
each bit is described below. Refer to
Optical
and
Wired Remote I/O System
Manuals
for details.
If there are errors in more than one Remote I/O Unit, word 251 will error in-
formation for only the first one. Data for the remaining Units will be stored in
memory and can be accessed by turning the Error Check bit ON and OFF.
Be sure to record data for the first error, which will be cleared when data for
the next error is displayed.
Not used.
Bit 03 turns ON when an error has occurred in a Remote I/O Unit.
Bit 00 - Error Check Bit
Bits 01 and 02
Bit 03 - Remote I/O Error
Flag
SR Area
Section 3-4
