Interrupt Descriptions
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ADSP-BF535 Blackfin Processor Hardware Reference
USB Endpoint Interrupts
Each endpoint interrupt in the USB General Interrupt register is based on
the interrupt status of all interrupt sources for the endpoint. If any of the
endpoint interrupts is active and unmasked, an interrupt is generated and
sets the corresponding bit in the Global Interrupt register (
USBD_GINTR
).
The individual interrupt behaviors are described in the following sections.
Note that it is possible to cause the top-tier interrupt to retrigger by tog-
gling the mask bit for the endpoint interrupts.
USBD_TC – Transfer Complete
The
USBD_TC
interrupt asserts when a transfer completes on the current
endpoint. Because the USB protocol does not maintain a transfer count,
the end of a transfer is assumed whenever a short packet is transferred on
an endpoint. The USB protocol requires all bulk interrupt and control
endpoints to transmit the maximum sized packet for the endpoint (that is,
8, 16, 32, 64) until the end of a data transfer.
At the end of the transfer, the remaining bytes are transmitted in a short
packet. If the data transfer ends on a packet boundary, the short packet
can contain 0 bytes. The 0 byte packet is not required for isochronous
transfers.
This interrupt does not assert when a setup packet is received on a control
endpoint.
USBD_PC – Packet Complete
This interrupt asserts when a packet transfer completes on the current
endpoint. System software can use this interrupt to monitor the progress
of a data transfer.
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...