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231
ERTEC 200P-2 Manual
Technical data subject to change
Version 1.0
The group interrupts PN_IRQ2(
1:0
) (IRQ56/57) and 14 selectable single interrupts
PN_IRQ2(
15:2
) (IRQ58-71) are connected to the ARM926EJ-S interrupt controller (ARM-
ICU) by the PN-IP (see 2.3.2.14).
Interrupts for the host are generated by the event unit in the peripheral interface. The PN-
IP forwards the relevant interrupts (group interrupts: PN_IRQ3(
1:0
), single interrupts:
PN_IRQ3(
15:2
)) to the event unit, Where a group interrupt signal to the external host
(ASIC pin: XHIF_XIRQ) is generated.
The group interrupt PN_IRQx(
0/1:0
) is generated as shown below:
Figure 23: Block diagram of PN-ICU for PN_IRQx(0/1:0) group interrupts
For each group interrupt (2x for ARM926 / external host: PN_IRQ2/3(1:0): PN_IRQ1(0),
there is one interrupt controller. IRQEvent registers are implemented for signaling and
saving internal PN-IP events. The same events are connected to all interrupt controllers.
One or more event bits set can each trigger a group interrupt for the external CPU sub-
system
PN_IRQx(0/1:0). For all event bits, the interrupt is triggered by:
internal PN-IP events (PN-IP events)
OR
dedicated AHB write access to IRQEvent
OR
dedicated AHB write access (SW events over IRQ_Activate).
Event bits already written/set are retained and not reset by subsequent access to the
IRQEvent registers. The assignment and significance of the individual event bits is identi-
cal for all PN-ICUs (1..3).
The decision whether an interrupt event (set event bit) triggers the corresponding
PN_IRQx(0/1:0) group interrupt is configured with event bit masking with the IRQMask
registers. A set mask bit blocks the corresponding entry and prevents PN_IRQx(0/1:0)
from being triggered. Over the IRQ registers, the event bits that trigger a PN_IRQx(0/1:0)
group interrupt (IRQ bits) can then be read. Writing to these registers is ignored. The two
group interrupts are masked differently by the SW to create interrupt groups (e.g. acyclic
API and cyclic API by group).
Bits in the IRQEvent registers are reset by write access to the IRQAck registers. The PN-
ICU may only be operated in "
Acknowledge
" mode, i.e. the event bits set are estab-
lished with read access to the IRQ registers. Subsequent write access to the IRQAck
registers resets the register bits written in the IRQEvent registers and therefore also the
IRQ bits in the IRQ registers.
PN_IRQx(0/1:0) group interrupts are deactivated over the IRQ_EOI registers. Write ac-
cess to the registers resets the PN_IRQx(0/1:0) group interrupts. The PN_IRQx(0/1:0)
group interrupt cannot be reactivated by set event bits in the IRQEvent registers until the
wait time (Wait_Time) written is up.