Atmel ARM-Based Evaluation Kit AT91SAM9N12-EK AT91SAM9N12-EK Hoja De Datos
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AT91SAM9N12-EK
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SAM9N12/SAM9CN11/SAM9CN12 [DATASHEET]
11063K–ATARM–05-Nov-13
In order to select an additional interrupt mode:
The type of event detection (edge or level) must be selected by writing in the Edge Select register (PIO_ESR) and
Level Select register (PIO_LSR) which , respectively, the edge and level detection. The current status of this
selection is accessible through the Edge/Level Status register (PIO_ELSR).
Level Select register (PIO_LSR) which , respectively, the edge and level detection. The current status of this
selection is accessible through the Edge/Level Status register (PIO_ELSR).
The polarity of the event detection (rising/falling edge or high/low-level) must be selected by writing in the Falling
Edge /Low-Level Select register (PIO_FELLSR) and Rising Edge/High-Level Select register (PIO_REHLSR)
which allow to select falling or rising edge (if edge is selected in PIO_ELSR) edge or high- or low-level detection (if
level is selected in PIO_ELSR). The current status of this selection is accessible through the Fall/Rise - Low/High
Status register (PIO_FRLHSR).
Edge /Low-Level Select register (PIO_FELLSR) and Rising Edge/High-Level Select register (PIO_REHLSR)
which allow to select falling or rising edge (if edge is selected in PIO_ELSR) edge or high- or low-level detection (if
level is selected in PIO_ELSR). The current status of this selection is accessible through the Fall/Rise - Low/High
Status register (PIO_FRLHSR).
When an input edge or level is detected on an I/O line, the corresponding bit in the Interrupt Status register (PIO_ISR) is
set. If the corresponding bit in PIO_IMR is set, the PIO Controller interrupt line is asserted.The interrupt signals of the 32
channels are ORed-wired together to generate a single interrupt signal to the interrupt controller.
set. If the corresponding bit in PIO_IMR is set, the PIO Controller interrupt line is asserted.The interrupt signals of the 32
channels are ORed-wired together to generate a single interrupt signal to the interrupt controller.
When the software reads PIO_ISR, all the interrupts are automatically cleared. This signifies that all the interrupts that
are pending when PIO_ISR is read must be handled. When an Interrupt is enabled on a “level”, the interrupt is generated
as long as the interrupt source is not cleared, even if some read accesses in PIO_ISR are performed.
are pending when PIO_ISR is read must be handled. When an Interrupt is enabled on a “level”, the interrupt is generated
as long as the interrupt source is not cleared, even if some read accesses in PIO_ISR are performed.
Figure 23-7. Event Detector on Input Lines (Figure Represents Line 0)
23.5.10.1 Example
If generating an interrupt is required on the lines below, the configuration required is described in
,
and
Rising edge on PIO line 0
Falling edge on PIO line 1
Rising edge on PIO line 2
Low-level on PIO line 3
High-level on PIO line 4
High-level on PIO line 5
Falling edge on PIO line 6
Rising edge on PIO line 7
Any edge on the other lines
The required configuration is described below.
Event Detector
0
1
0
1
1
0
0
1
Edge
Detector
Falling Edge
Detector
Rising Edge
Detector
PIO_FELLSR[0]
PIO_FRLHSR[0]
PIO_REHLSR[0]
Low Level
Detector
High Level
Detector
PIO_ESR[0]
PIO_ELSR[0]
PIO_LSR[0]
PIO_AIMDR[0]
PIO_AIMMR[0]
PIO_AIMER[0]
Event detection on line 0
Resynchronized input on line 0