Datasheet

...........continued

Value Description

0x5 256 Byte

(1)

0x6 512 Byte

(1)

0x7 1023 Byte

(1)

(1) for Isochronous endpoints only.

Bits 27:14 – MULTI_PACKET_SIZE[13:0] 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.

Bits 13:0 – BYTE_COUNT[13:0] 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.

SAM D21 Family

USB – Universal Serial Bus

Datasheet Complete

DS40001882D-page 853