upd17225 Renesas Electronics Corporation., upd17225 Datasheet - Page 41

• Manufacturer Part Number: upd17225
• Description: 4-bit Single-chip Microcontroller For Small General-purpose Infrared Remote Control Transmitter
• Manufacturer: Renesas Electronics Corporation.

7.2
7.2.1
This section describes the flags of the interrupt control circuit.
(1) Interrupt request flag and interrupt enable flag
(2) EI/DI instruction
This flag reads the INT pin status.
When a high level is input to the INT pin, this flag is set to “1”; when a low level is input, the flag is reset to “0”.
Hardware of Interrupt Control Circuit
The interrupt request flag (IRQ
cleared to 0 when the interrupt processing is excuted.
An interrupt enable flag (IP
is enabled; when it is 0, the interrupt is disabled.
Whether an accepted interrupt is executed or not is specified by the EI or DI instruction.
When the EI instruction is executed, INTE (interrupt enable flag), which enables the interrupt, is set to 1. The
INTE flag is not registered on the register file. Consequently, the status of this flag cannot be checked by
an instruction.
The DI flag clears the INTE flag to 0 to disable all the interrupts.
The INTE flag is also cleared to 0 at reset, disabling all the interrupts.
INT
3
0
IRQTM
IRQ
IRQBTM
Request Flag
Interrupt
0
2
Table 7-2. Interrupt Request Flags and Interrupt Enable Flag
Reset by 8-bit timer.
Set when edge of INT pin input signal is detected
Reset by basic interval timer.
0
1
) is provided to each interrupt request flag. When the IPxxx flag is 1, the interrupt
INT
Signal Setting Interrupt Request Flag
0
) is set to 1 when an interrupt request is generated, and is automatically
Data Sheet U12643EJ2V0DS00
RF : 0FH
Address
INT
0
1
INT Pin Level Detection
INT pin : Low level
INT pin : High level
Undefined
On reset
PD17225, 17226, 17227, 17228
R/W
R
IPTM
IP
IPBTM
Enable Flag
Interrupt
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