Rockwell Automation 1761 MicroLogix 1000 Programmable Controllers - Manual (Page 292)

Preface MicroLogix 1000 Programmable Controllers User Manual
B–4
Address Description Classification Bit
S:0/2 Zero Status This bit is set by the controller when the result
of certain math or data handling instructions is
zero. Otherwise the bit remains cleared.
When a STI, high-speed counter, or Fault
Routine interrupts normal execution of your
program, the original value of S:0/2 is restored
when execution resumes.
S:0/3 Sign Status This bit is set by the controller when the result
of certain math or data handling instructions is
negative. Otherwise the bit remains cleared.
When a STI, high-speed counter, or Fault
Routine interrupts normal execution of your
program, the original value of S:0/3 is restored
when execution resumes.
S:0/4 to
S:0/7 Reserved NA NA
S:0/8
➀
Extend I/O
Configuration Static
Configuration This bit must be set by the user when unused
outputs are written to. If reset and unused
outputs are turned on the controller will fault
(41H).
S:0/9 Reserved NA NA
S:0/10 Primary
Protocol Static
Configuration This bit defines the protocol that the controller
will initially use when attempting to establish
communication, where:
0 = DF1 (default setting)
1 = DH-485
S:0/11 Active
Protocol Status This bit is updated by the controller during a
protocol switch. It indicates which protocol is
currently being used for communication,
where:
0 = DF1
1 = DH-485
S:0/12 Selected DF1
Protocol Status This bit allows the user to determine which
DF1 protocol is configured, where:
0 = DF1 Full-Duplex (default setting)
1 = DF1 Half-Duplex Slave
S:0/13 to
S:0/15 Reserved NA NA
➀
Valid for Series A–C discrete only.