Interrupt Descriptions
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ADSP-BF535 Blackfin Processor Hardware Reference
Software can mask each interrupt individually. Under this scheme, it is
possible to enable software polling of the interrupts or to enable the hard-
ware interrupt.
USB General Interrupts
The general interrupts are the top tier of the interrupt subsystem. This tier
has the general interrupts and an interrupt for each endpoint.
USBD_SOF – Start of Frame
The
USBD_SOF
interrupt indicates that the USB device has received a Start
of Frame (SOF) token from the USB host. The USB host broadcasts the
SOF token at 1.0 ms intervals as a timebase for isochronous transfers. Iso-
chronous endpoints can use this interrupt as part of their synchronization
mechanism.
USBD_CFG – USB Configuration Change
The
USBD_CFG
interrupt indicates to the device that a configuration change
event occurred on the USB. The host has requested the device to change
to a different configuration, or it has switched to a different alternate
interface for one of the interfaces in the current configuration.
Timely service of this interrupt is critical to ensure proper device
operation. Once this interrupt is received, the software must imme-
diately reconfigure itself to match the new configuration settings,
then clear the interrupt.
To prevent the device’s configuration from becoming out of sync with the
intended configuration (from the USB host’s viewpoint), the device
refuses all traffic from the USB while the interrupt is pending. Masking
the interrupt does not disable the USB activity lockout feature.
Summary of Contents for ADSP-BF535 Blackfin
Page 80: ...Development Tools 1 26 ADSP BF535 Blackfin Processor Hardware Reference...
Page 312: ...Working With Memory 6 86 ADSP BF535 Blackfin Processor Hardware Reference...
Page 332: ...System Interfaces 7 20 ADSP BF535 Blackfin Processor Hardware Reference...
Page 360: ...Dynamic Power Management Controller 8 28 ADSP BF535 Blackfin Processor Hardware Reference...
Page 446: ...Beginning and Ending an SPI Transfer 10 40 ADSP BF535 Blackfin Processor Hardware Reference...
Page 522: ...Timing Examples 11 76 ADSP BF535 Blackfin Processor Hardware Reference...
Page 562: ...IrDA Support 12 40 ADSP BF535 Blackfin Processor Hardware Reference...
Page 608: ...PCI I O Issues 13 46 ADSP BF535 Blackfin Processor Hardware Reference...
Page 672: ...References 14 64 ADSP BF535 Blackfin Processor Hardware Reference...
Page 810: ...SDRAM Controller SDC 18 86 ADSP BF535 Blackfin Processor Hardware Reference...
Page 811: ...ADSP BF535 Blackfin Processor Hardware Reference 18 87 External Bus Interface Unit...
Page 812: ...SDRAM Controller SDC 18 88 ADSP BF535 Blackfin Processor Hardware Reference...
Page 860: ...DMA Bus Debug Registers 20 30 ADSP BF535 Blackfin Processor Hardware Reference...