Data Sheet

806
Atmel | SMART SAM D21 [DATASHEET]
Atmel-42181G–SAM-D21_Datasheet–09/2015
z Bits 27:14 – MULTI_PACKET_SIZE: Multiple Packet Size
These bits define the 14-bit value that is used for multi-packet transfers.
For IN endpoints, MULTI_PACKET_SIZE holds the total number of bytes sent. MULTI_PACKET_SIZE should be
written to zero when setting up a new transfer.
For OUT endpoints, 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 is used for the byte count.
For IN endpoints, BYTE_COUNT holds the number of bytes to be sent in the next IN transaction.
For OUT endpoint or SETUP endpoints, BYTE_COUNT holds the number of bytes received upon the last OUT or
SETUP transaction.
Table 31-16. Endpoint Size
SIZE[2:0] Description
0x0 8 Byte
0x1 16 Byte
0x2 32 Byte
0x3 64 Byte
0x4 128 Byte
(1)
1. for Isochronous endpoints only.
0x5 256 Byte (1)
0x6 512 Byte (1)
0x7 1023 Byte (1)