General-Purpose I/O
10-10
The interrupt control register allows the user to define when an interrupt
request occurs. The interrupt can either be generated from a high-to-low tran-
sition (function 0) or a low-to-high transition (function 1).
Table 10–6. Interrupt Control Register (INTERRUPT_CONTROL_REG)
Bit
Value
Function
Access
(R/W)
Reset
Value
15–0
0
Selects high to low transition
R/W
0xFFFF
1
Selects low to high transition
The interrupt mask register allows the user to mask(disable) certain input pins
from generating an interrupt request.
Table 10–7. Interrupt Mask Register (INTERRUPT_MASK_REG)
Bit
Value
Function
Access
(R/W)
Reset
Value
15–0
0
Enables interrupt
R/W
0xFFFF
1
Disables interrupt
The interrupt status register is used to determine which of the input pins
requested an interrupt. Bit 0 corresponds to GPIO0 and so forth. If the value
is a 1, then that pin is requesting the interrupt. The processor services the inter-
rupt and resets the appropriate bit in the status register. If the user wants to
reset the status bit, then a 1 must be written to the appropriate bit. However,
the user can not generate an interrupt by writing a 1 to the interrupt status
register. If the user writes a 0 to a bit in the status register, the value remains
unchanged.
Table 10–8. Interrupt Status Register (INTERRUPT_STATUS_REG)
Bit
Value
Function
Access
(R/W)
Reset
Value
15–0
0
0: No interrupt request
R/W
0x0000
1
An interrupt has been requested