Allen-Bradley MicroLogix 1200 Reference Manual page 233

Table 18.10 Selectable Timed Interrupt Function File (STI:0)
Sub-Element Description
PFN - Program File Number
ER - Error Code
UIX - User Interrupt Executing
UIE - User Interrupt Enable
UIL - User Interrupt Lost
UIP - User Interrupt Pending
TIE - Timed Interrupt Enabled
AS - Auto Start
ED - Error Detected
SPM - Set Point Msec
Selectable Time Interrupt (STI) Function File Sub-Elements Summary
Address Data Format
STI:0.PFN word (INT)
STI:0.ER word (INT)
STI:0/UIX binary (bit)
STI:0/UIE binary (bit)
STI:0/UIL binary (bit)
STI:0/UIP binary (bit)
STI:0/TIE binary (bit)
STI:0/AS binary (bit)
STI:0/ED binary (bit)
STI:0.SPM word (INT)
STI Function File Sub-Elements
STI Program File Number (PFN)
Sub-Element Description
PFN - Program File Number
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)
Sub-Element Description
ER - Error Code
Error codes detected by the STI sub-system are displayed in this register.
The table below explains the error codes.
Table 18.11 STI Error Code
Error Recoverable Fault
Code (Controller)
1 Invalid Program File
Number
Type User Program
Access
control read only
status read only
status read only
control read/write
status read/write
status read only
control read/write
control read only
status read only
control read/write
Address Data Format Type
STI:0.PFN word (INT)
Address Data Format Type
STI:0.ER word (INT)
Description
Program file number is less than 3, greater than 255, or does not
exist.
Using Interrupts 18-13
For More
Information
18-13
18-13
18-14
18-14
18-14
18-15
18-15
18-15
18-16
18-16
User Program
Access
control read only
User Program
Access
status read only
Publication 1762-RM001C-EN-P