Atmel Xplained Pro Evaluation Kit for the ATSAMD21J18A Microcontroller ATSAMD21-XPRO ATSAMD21-XPRO Data Sheet
Product codes
ATSAMD21-XPRO
826
Atmel | SMART SAM D21 [DATASHEET]
Atmel-42181C–SAM-D21_Datasheet–07/2014
(1) for Isochronous pipe only.
z
Bits 27:14 – MULTI_PACKET_SIZE: Multi Packet IN or OUT size
These bits define the 14-bit value that is used for multi-packet transfers.
For IN pipes, MULTI_PACKET_SIZE holds the total number of bytes sent. MULTI_PACKET_SIZE should be writ-
ten to zero when setting up a new transfer.
For OUT pipes, MULTI_PACKET_SIZE holds the total data size for the complete transfer. This value must be a
multiple of the maximum packet size.
These bits define the 14-bit value that is used for multi-packet transfers.
For IN pipes, MULTI_PACKET_SIZE holds the total number of bytes sent. MULTI_PACKET_SIZE should be writ-
ten to zero when setting up a new transfer.
For OUT pipes, MULTI_PACKET_SIZE holds the total data size for the complete transfer. This value must be a
multiple of the maximum packet size.
z
Bits 13:0 – BYTE_COUNT: Byte Count
These bits define the 14-bit value that contains number of bytes sent in the last OUT or SETUP transaction for an
OUT pipe, or of the number of bytes to be received in the next IN transaction for an input pipe.
These bits define the 14-bit value that contains number of bytes sent in the last OUT or SETUP transaction for an
OUT pipe, or of the number of bytes to be received in the next IN transaction for an input pipe.
Table 31-28. Pipe Size
SIZE[2:0]
Description
0x0
8 Byte
0x1
16 Byte
0x2
32 Byte
0x3
64 Byte
0x4
128 Byte
(1)
0x5
256 Byte
(1)
0x6
512 Byte
(1)
0x7
1024 Byte in HS mode
(1)
1023 Byte in FS mode
(1)