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11. Interrupts
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External Interrupt Request Source Select Register
Symbol
Address
After Reset
IFSR
031F16
0016
RW
INT0 Interrupt Polarity
Select Bit(1)
INT1 Interrupt Polarity
Select Bit(1)
INT2 Interrupt Polarity
Select Bit(1)
INT3 Interrupt Polarity
Select Bit(1)
INT4 Interrupt Polarity
select bit(1)
INT5 Interrupt Polarity
Select Bit(1)
0 : One edge
1 : Both edges
0 : One edge
1 : Both edges
0 : One edge
1 : Both edges
0 : One edge
1 : Both edges
0 : One edge
1 : Both edges
Bit Name
Bit
Symbol
Function
NOTES:
1. Set this bit to "0" to select a level-sensitive triggering.
When setting this bit to "1", set the POL bit in the INTilC register (i = 0 to 5) to "0" (falling edge).
UART1, UART4
Interrupt Source
Select Bit
UART0, UART3
Interrupt Source
Select Bit
0 : One edge
1 : Both edges
IFSR3
IFSR4
IFSR5
IFSR6
IFSR0
IFSR2
IFSR1
IFSR7
RW
0 : UART3 bus conflict, start condition
detect, stop condition detect
1 : UART0 bus conflict, start condition
detect, stop condition detect
0 : UART4 bus conflict, start condition
detect, stop condition detect
1 : UART1 bus conflict, start condition
detect, stop condition detect
b7
b6
b5
b4
b3
b2
b1
b0
______
11.7 INT Interrupt
______
External input generates the INTi interrupt (i = 0 to 5). The LVS bit in the INTiIC register selects either edge
sensitive triggering to generate an interrupt on any edge or level sensitive triggering to generate an inter-
rupt at an applied signal level. The POL bit in the INTiIC register determines the polarity.
For edge sensitive, when the IFSRi bit in the IFSR register is set to "1", an interrupt occurs on both rising
and falling edges of the external input. If the IFSRi bit is set to "1", set the POL bit in the corresponding
register to "0" (falling edge).
_______
For level sensitive, set the IFSRi bit to "0" (single edge). When the INTi pin input level reaches the level set
_______
in the POL bit, the IR bit in the INTiIC register is set to "1". The IR bit remains unchanged even if the INTi
_______
pin level is changed. The IR bit is set to "0" when the INTi interrupt is acknowledged or when the IR bit is
written to "0" by program.
Figure 11.10 shows the IFSR register.
Figure 11.10 IFSR Register