703
32072H–AVR32–10/2012
AT32UC3A3
An underflow can occur during IN stage if the host attempts to read from an empty bank. A zero-length packet is then
automatically sent by the USBB.
An underflow can also occur during OUT stage if the host sends a packet while the bank is already full. Typically, the CPU is not
fast enough. The packet is lost.
Shall be cleared by writing a one to the UNDERFIC bit. This will acknowledge the interrupt.
This bit is inactive (cleared) for bulk and interrupt IN/OUT endpoints and it means RXSTPI for control endpoints.
• RXSTPI: Received SETUP Interrupt
This bit is set, for control endpoints, to signal that the current bank contains a new valid SETUP packet. This triggers an EPnINT
interrupt if RXSTPE is one.
Shall be cleared by writing a one to the RXSTPIC bit. This will acknowledge the interrupt and free the bank.
This bit is inactive (cleared) for bulk and interrupt IN/OUT endpoints and it means UNDERFI for isochronous IN/OUT endpoints.
• RXOUTI: Received OUT Data Interrupt
This bit is set, for control endpoints, when the current bank contains a bulk OUT packet (data or status stage). This triggers an
EPnINT interrupt if RXOUTE is one.
Shall be cleared for control end points, by writing a one to the RXOUTIC bit. This will acknowledge the interrupt and free the
bank.
This bit is set for isochronous, bulk and, interrupt OUT endpoints, at the same time as FIFOCON when the current bank is full.
This triggers an EPnINT interrupt if RXOUTE is one.
Shall be cleared for isochronous, bulk and, interrupt OUT endpoints, by writing a one to the RXOUTIC bit. This will acknowledge
the interrupt, what has no effect on the endpoint FIFO.
The user then reads from the FIFO and clears the FIFOCON bit to free the bank. If the OUT endpoint is composed of multiple
banks, this also switches to the next bank. The RXOUTI and FIFOCON bits are set/cleared in accordance with the status of the
next bank.
RXOUTI shall always be cleared before clearing FIFOCON.
This bit is inactive (cleared) for isochronous, bulk and interrupt IN endpoints.
• TXINI: Transmitted IN Data Interrupt
This bit is set for control endpoints, when the current bank is ready to accept a new IN packet. This triggers an EPnINT interrupt
if TXINE is one.
This bit is cleared when the TXINIC bit is written to one. This will acknowledge the interrupt and send the packet.
This bit is set for isochronous, bulk and interrupt IN endpoints, at the same time as FIFOCON when the current bank is free.
This triggers an EPnINT interrupt if TXINE is one.
This bit is cleared when the TXINIC bit is written to one. This will acknowledge the interrupt, what has no effect on the endpoint
FIFO.
The user then writes into the FIFO and clears the FIFOCON bit to allow the USBB to send the data. If the IN endpoint is
composed of multiple banks, this also switches to the next bank. The TXINI and FIFOCON bits are set/cleared in accordance
with the status of the next bank.
TXINI shall always be cleared before clearing FIFOCON.
This bit is inactive (cleared) for isochronous, bulk and interrupt OUT endpoints.
Summary of Contents for AT32UC3A3128
Page 61: ...61 32072H AVR32 10 2012 AT32UC3A3 PLLEN PLL Enable 0 PLL is disabled 1 PLL is enabled...
Page 592: ...592 32072H AVR32 10 2012 AT32UC3A3 Manchester Configuration Register on page 614...
Page 989: ...989 32072H AVR32 10 2012 AT32UC3A3 37 2 Package Drawings Figure 37 1 TFBGA 144 package drawing...
Page 991: ...991 32072H AVR32 10 2012 AT32UC3A3 Figure 37 3 VFBGA 100 package drawing...
