Allen-Bradley MicroLogix 1200 Reference Manual

Publication 1762-RM001C-EN-P
Using Interrupts 18-13
Selectable Time Interrupt (STI) Function File Sub-Elements Summary
STI Function File Sub-Elements
STI Program File Number (PFN)
The PFN (Program File Number) variable defines which subroutine is
called (executed) when the timed interrupt times out. A valid subroutine
file is any program file (3 to 255).
The subroutine file identified in the PFN variable is not a special file
within the controller; it is programmed and operates the same as any
other program file. From the control program perspective it is unique, in
that it is automatically scanned based on the STI set point.
STI Error Code (ER)
Error codes detected by the STI sub-system are displayed in this register.
The table below explains the error codes.
Table 18.10 Selectable Timed Interrupt Function File (STI:0)
Sub-Element Description Address Data Format Type User Program
Access
For More
Information
PFN - Program File Number STI:0.PFN word (INT) control read only 18-13
ER - Error Code STI:0.ER word (INT) status read only 18-13
UIX - User Interrupt Executing STI:0/UIX binary (bit) status read only 18-14
UIE - User Interrupt Enable STI:0/UIE binary (bit) control read/write 18-14
UIL - User Interrupt Lost STI:0/UIL binary (bit) status read/write 18-14
UIP - User Interrupt Pending STI:0/UIP binary (bit) status read only 18-15
TIE - Timed Interrupt Enabled STI:0/TIE binary (bit) control read/write 18-15
AS - Auto Start STI:0/AS binary (bit) control read only 18-15
ED - Error Detected STI:0/ED binary (bit) status read only 18-16
SPM - Set Point Msec STI:0.SPM word (INT) control read/write 18-16
Sub-Element Description Address Data Format Type User Program
Access
PFN - Program File Number STI:0.PFN word (INT) control read only
Sub-Element Description Address Data Format Type User Program
Access
ER - Error Code STI:0.ER word (INT) status read only
Table 18.11 STI Error Code
Error
Code
Recoverable Fault
(Controller)
Description
1 Invalid Program File
Number
Program file number is less than 3, greater than 255, or does not
exist.

Allen-Bradley MicroLogix 1200 Specifications

General

Series	MicroLogix 1200
Type	Programmable Logic Controller (PLC)
Mounting	DIN rail or panel mount
Programming Language	Ladder Logic
Programming Software	RSLogix 500
I/O Points	Up to 40
Communication Ports	RS-232, RS-485
Memory	6 KB user memory
Power Supply	24V DC or 120/240V AC
Expansion	Supports expansion I/O modules
Operating Temperature	0°C to 55°C (32°F to 131°F)
Dimensions	90 mm x 110 mm
Weight	0.5 kg (1.1 lbs)