Specifications

Operation IP 240
5.1 Settings for Interrupt Generation
The processing of interrupt signals makes it possible to respond rapidly to status changes.
In the SIMATIC S5 programmable controllers, a distinction is made between two types of inter-
rupts:
•
”Servicing IRx interrupt circuits” (S5-115U, S5-135U and S5-155U in the 155U mode)
•
”Reading I/O byte 0” (S5-150U and S5-155U in the 150U mode).
5.1.1 IRx Interrupt Circuits
The interrupt signal generated on the IP 240 can be routed to the S5-CPU via one of four
interrupt circuits IRA to IRD for interrupt processing. The following must be taken into account:
• the possible slots on the IP 240 ( Section 4.1.2)
•
the capabilities of the programmable controllers and individual CPUs ( Table 5-1)
• the required switch settings on the IP 240
Fig. 5-2. Allocation of Coding Switches on Switchbank S2 to the IRx Interrupt Circuits
PLC CPU CPU slot Serviceable interrupt circuit
S5-115U 941 IRA, IRB
942, 943, 944 IRA, IRB, IRC, IRD
S5-135U 922 or 928 11 IRA
922 or 928 19 IRB
922 or 928 27 IRC
922 or 928 35 IRD
S5-155U 946/947, 922 or 928 11 IRA
(155U mode) 946/947, 922 or 928 51 IRB
922 or 928 91 IRC
922 or 928 99 IRD
Coding switches S2.1 to S2.4
on : the corresponding interrupt circuit is used
off: the corresponding interrupt circuit is not used
IRD
IRC
IRB
IRA
321 4
on
off
Allocation of coding switches on switchbank S2 to the IRx interrupt circuits
Use coding switches S2.1 to S2.4 to set the IRx interrupt circuit to be used.
Switchbank S2
Table 5-1. Allocation of Serviceable Interrupt Circuits
5-2 EWA 4NEB 811 6120-02a