ADSP-BF535 Blackfin Processor Hardware Reference
15-5
Programmable Flags
Flag Interrupt Mask Registers
(FIO_MASKA_C, FIO_MASKA_S,
FIO_MASKB_C, FIO_MASKB_S)
Like the Flag Set and Flag Clear registers, the Flag Interrupt Mask regis-
ters are implemented as complementary pairs of write-1-to-set and
write-1-to-clear registers. This implementation provides the ability to
enable or disable a
PFx
pin to act as a processor interrupt without requir-
ing read-modify-write accesses.
Flag Interrupt A and Flag Interrupt B are each supported by a dedicated
Flag Interrupt Mask Set register and a Flag Interrupt Mask Clear register
(see
Figure 15-4
,
Figure 15-5
,
Figure 15-6
, and
Figure 15-7
). Each
PFx
pin is represented by a bit in each of the four registers. Writing a 1 to a bit
in a mask set register enables interrupt generation for that
PFx
pin, while
writing a 1 to a bit in a mask clear register disables interrupt generation
for that
PFx
pin.
Interrupt A and Interrupt B operate independently. For example, writing
a 1 to a bit in the Flag Interrupt A Mask Set register does not affect Flag
Interrupt B. This facility allows
PFx
pins to generate Flag Interrupt A, Flag
Interrupt B, both Flag Interrupts A and B, or neither.
When using either rising or falling edge-triggered interrupts, the interrupt
condition must be cleared each time a corresponding interrupt is serviced
by writing a 1 to the appropriate
FIO_FLAG_C
bit.
Содержание ADSP-BF535 Blackfin
Страница 80: ...Development Tools 1 26 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 312: ...Working With Memory 6 86 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 332: ...System Interfaces 7 20 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 360: ...Dynamic Power Management Controller 8 28 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 446: ...Beginning and Ending an SPI Transfer 10 40 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 522: ...Timing Examples 11 76 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 562: ...IrDA Support 12 40 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 608: ...PCI I O Issues 13 46 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 672: ...References 14 64 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 810: ...SDRAM Controller SDC 18 86 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 811: ...ADSP BF535 Blackfin Processor Hardware Reference 18 87 External Bus Interface Unit...
Страница 812: ...SDRAM Controller SDC 18 88 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 860: ...DMA Bus Debug Registers 20 30 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 908: ...SDRAM Controller External Bus Interface Unit B 36 ADSP BF535 Blackfin Processor Hardware Reference...