Samsung S5PC110 Manual page 160

S5PC110_UM
2.2.55 GPIO INTERRUPT CONTROL REGISTERS
GPIO Interrupt comprise of 22 groups, namely, GPA0, GPA1, GPB, GPC0, GPC1, GPD0, GPD1, GPE0, GPE1,
GPF0, GPF1, GPF2, GPF3, GPG0, GPG1, GPG2, GPG3, GPJ0, GPJ1, GPJ2, GPJ3 and GPJ4.
In interrupt function, it is important to understand the filter operation.
S5PC110 uses two types of filters to detect interrupt, namely, delay filter and digital filter.
Delay filter uses delay cell.
If clock is not serviced, select the delay filter in alive area.
Delay filter enables to detect interrupt after 35ns from the time when the interrupt occurs.
Digital filter means that all interrupt counts are based on clock.
Therefore, this filter can be used in clock-supported area.(both off area and alive area)
When you select digital filter set the filtering width.
Digital filter can detect interrupt per every clock count as many as filtering width.
Filtering width is 6-bit in alive area and is 7-bit in off area.
When you use interrupt function, set either delay or digital filter enabled in order to detect interrupt.
If filter is disabled, there is strong probability that system detects all interrupt from successive interrupts (Some
interrupt detection will be missed).
To detect all interrupts stably, you had better set filter enable.
GPIO Interrupt cannot use for wake-up source. For wake-up interrupt source, you can use External interrupt.
The following table shows the list of GPIO Interrupt control registers.
Register
GPA0_INT_CON
GPA1_INT_CON
GPB_INT_CON
GPC0_INT_CON
GPC1_INT_CON
GPD0_INT_CON
GPD1_INT_CON
GPE0_INT_CON
Address R/W
0xE020_0700 R/W
0xE020_0704 R/W
0xE020_0708 R/W
0xE020_070C R/W
0xE020_0710 R/W
0xE020_0714 R/W
0xE020_0718 R/W
0xE020_071C R/W
2 GENERAL PURPOSE INPUT/ OUTPUT
Description
GPIO Interrupt GPA0_INT Configuration
Register
GPIO Interrupt GPA1_INT Configuration
Register
GPIO Interrupt GPB_INT Configuration
Register
GPIO Interrupt GPC0_INT Configuration
Register
GPIO Interrupt GPC1_INT Configuration
Register
GPIO Interrupt GPD0_INT Configuration
Register
GPIO Interrupt GPD1_INT Configuration
Register
GPIO Interrupt GPE0_INT Configuration
Reset Value
0x0
0x0
0x0
0x0
0x0
0x0
0x0
0x0
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