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CHAPTER 14 DTP/EXTERNAL INTERRUPT CIRCUIT
14.1 Overview of the DTP/External Interrupt Circuit
The data transfer peripheral (DTP)/external interrupt circuit detects interrupt request
input from the external interrupt input pins (INT7 to INT0) to output interrupt requests.
s DTP/External Interrupt Circuit Functions
The DTP/external interrupt circuit function outputs an interrupt request when it detects an edge
or level signal input to the external interrupt input pins (INT7 to INT0).
When an interrupt request is accepted by the CPU and the extended intelligent I/O service
(EI2OP) is enabled, the automatic data transfer (DTP function) is performed by EI2OP before
branching to the interrupt processing routine. If EI2OP is disabled, the automatic data transfer
(DTP function) by EI2OP is not activated; instead, direct branching to the interrupt processing
routine takes place.
Table 14.1-1 Overview of the DTP/External Interrupt Circuit
External interrupt function
DTP function
Input pins
Eight (P10/INT0 to P16/INT6 and P63/INT7/DTTI)
Interrupt cause
By using the request level setting register (ELVR), the detection level
or edge type can be set for each pin.
Input of the "L" level/"H" level/rising edge/falling edge
Interrupt number
#25 (19H) - #28 (1CH)
Interrupt control
The output of interrupt requests is enabled and disabled using the
DTP/interrupt enable register (ENIR).
Interrupt flag
Interrupt causes are stored in the DTP/interrupt cause register (EIRR).
Processing
selection
EI2OS is disabled (ICR: ISE = 0).
EI2OS is enabled (ICR: ISE = 1).
Processing
The circuit branches to an
external interrupt processing
routine.
Branching to the interrupt
processing routine after
automatic data transfer by EI2OS
ICR: Interrupt control register