Interrupt Service Routine (ISR) Flowcharts
13-111
USB Function Module
Figure 13–33. Read Isochronous RX FIFO Data Flowchart
ISO RX handler
Read byte from
DATA (RX FIFO).
Loop_count = 0?
Place byte in
application’s RX buffer.
Increment RX byte
count, decrement loop
count.
Update application’s
RX buffer count.
Yes
End of RX ISO Handler
Loop_count =
RXFSTAT.RXF_Count
STAT_FLG.
Data_Flush
=1?
Application-
specific actions
to handle case
for data flush
No
Yes
STAT_FLG.
ISO_Error
=1?
Application-
specific actions
to handle
unrecovered
ISO packet
Yes
No
STAT_FLG.
ISO_FIFO_Empty
=1?
Application-
specific actions
to handle
empty ISO
packet (or no
packet)
Yes
No (must be valid data)
No