Atmel SAM4L Xplained Pro Starter Kit Atmel ATSAM4L-XSTK ATSAM4L-XSTK Data Sheet
Product codes
ATSAM4L-XSTK
364
42023E–SAM–07/2013
ATSAM4L8/L4/L2
• The control and status fields for the pipe and bank (Pn_CTR_STA_BK0/1):
Table 17-6.
Pn_CTR_STA_BK0/1 structure
– UNDERF: Underflow status for isochronous/Interrupt IN transfers. This status bit is
set by hardware at the current bank (where the IN packet should have been stored).
When a new successful transaction occurs this bit is overwritten to zero if
UPSTAX.ERRORFI has previously been cleared by software. See
When a new successful transaction occurs this bit is overwritten to zero if
UPSTAX.ERRORFI has previously been cleared by software. See
– OVERF: Overflow status for isochronous/interrupt OUT transfers. This status bit is
set by hardware at the current bank (where the OUT packet should have been
loaded). When a new successful transaction occurs this bit is overwritten to zero if
UPSTAX.ERRORFI has previously been cleared by software. See
loaded). When a new successful transaction occurs this bit is overwritten to zero if
UPSTAX.ERRORFI has previously been cleared by software. See
– CRCERR: CRC error status for isochronous IN transfers. See
.
• The control and status 1 of endpoint n (Pn_CTR_STA1):
Table 17-7.
Pn_CTR_STA1 structure
– PERSTA: Pipe Error Status. See
table.
–
PERMAX
) is larger than PERMAX, the UPSTAX.PERRI bit is set.
–
PEPNUM
: Should be set by the user. Endpoint number for this pipe.
– PDADDR: Should be set by the user. Device address for this pipe.
Table 17-8.
PERSTA structure
This field can be cleared by software. To avoid read-modify-write issues, the user should: freeze
the pipe, wait until the UPSTAX.PFREEZE is one, clear the PERSTA field in memory, and then
unfreeze the pipe.
the pipe, wait until the UPSTAX.PFREEZE is one, clear the PERSTA field in memory, and then
unfreeze the pipe.
– ERCNT: Pipe Error Counter.
– CRC16ER: Is set if a CRC16 error occurs during an isochronous IN transaction.
– TOUTER: Is set if a Time-out error occurs during a USB transaction.
– PIDER: Is set if a PID error occurs during a USB transaction.
– DAPIDER: Is set if a Data PID error occurs during a USB transaction.
31:19
18
17
16
15:0
Status
Control
-
UNDERF
OVERF
CRCERR
-
31:24
23:16
15:12
11:8
7
6:0
Status
Control
-
PERSTA
PERMAX
PEPNUM
-
PDADDR
23:21
20
19
18
17
16
ERCNT
CRC16ER
TOUTER
PIDER
DAPIDER
DTGLER