Atmel ARM-Based Evaluation Kit AT91SAM9N12-EK AT91SAM9N12-EK Data Sheet

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SAM9N12/SAM9CN11/SAM9CN12 [DATASHEET]

11063K–ATARM–05-Nov-13

As indicated below, transfers are sequential events carried out on the USB bus.

Notes: 1.

Control transfer must use endpoints with no ping-pong attributes. 

2.

Isochronous transfers must use endpoints with ping-pong attributes.

3.

Control transfers can be aborted using a stall handshake.

A status transaction is a special type of host-to-device transaction used only in a control transfer. The control transfer
must be performed using endpoints with no ping-pong attributes. According to the control sequence (read or write), the
USB device sends or receives a status transaction.

Control Transfers

 



Setup transaction > Data IN transactions > Status 
OUT transaction



Setup transaction > Data OUT transactions > Status 
IN transaction



Setup transaction > Status IN transaction

Interrupt IN Transfer

(device toward host)



Data IN transaction > Data IN transaction

Interrupt OUT Transfer

(host toward device)



Data OUT transaction > Data OUT transaction

Isochronous

 

IN Transfer

(device toward host)



Data IN transaction > Data IN transaction

Isochronous OUT Transfer

(host toward device)



Data OUT transaction > Data OUT transaction

Bulk IN Transfer 

(device toward host)



Data IN transaction > Data IN transaction

Bulk OUT Transfer

(host toward device)



Data OUT transaction > Data OUT transaction