Siemens SIMATIC S5 Equipment Manual

Operating Instructions
R 02/92
2.6.1 Interru t Processing with Standard Function Block FB 157
(PER:#ST)
When an interrupt occurs, the interrupt OB2 is called. The call for the function block FB 157 with the
parameter assignment BEF = KB is written into this organization block.
After the call by the interrupt
OB, parameter ST shows from which channel the interrupt originated
(i.e., you can have your specific interrupt program processed then).
If, during the processing of function block FB 157 in the cyclic program, an interrupt occurs, the
group interrupt at the bus is cancelled again by FB 157 (or by reading byte 7). This interrupt is not
lost when the recommended programming for interrupt
OB2 is followed (see example in section
2.3).
2.6.2 Save and Reload Scratchpad Flags
In the S5–135U, OBS with special integrated functions are available for saving and reloading
scratchpad flags. For CPU 922 (version A09 or later) and for CPU 928, these OBS are OB 192 (for
saving) and OB 193 (for reloading).
here only to interrupts and not to timed interrupts.
Because of this, saving and reloading scratchpad flags is necessary only during a warm restart.
2 – 12
1P 241 Equipment Manual
@ Siemens AG 1989, Order No.: 6ES5 998-0KD21
Artisan Technology Group - Quality Instrumentation ... Guaranteed | (888) 88-SOURCE | www.artisantg.com

Siemens SIMATIC S5 Specifications

General

Product type designation	SIMATIC S5
Programming language	STEP 5
Digital inputs	Varies by model
Digital outputs	Varies by model
Analog inputs	Varies by model
Analog outputs	Varies by model
Supply voltage	24V DC
CPU Type	Varies by model
Memory	Varies by model
Digital I/O	Varies by model
Analog I/O	Varies by model
Communication	PROFIBUS
Operating Temperature	0°C to 60°C
Relative Humidity	5% to 95% (non-condensing)