beautypg.com

Chart – Texas Instruments TMS320DM357 User Manual

Page 49

background image

3.2.1.4

IN Status Phase (following SETUP Phase or OUT Data Phase)

IN token sent

?

received

STALL

No

Yes

Yes

No

RxStall set

ReqPkt cleared

Error Count cleared

Interrupt generated

Yes

?

Data1

received

Transaction

complete

No

NAK

received

?

Yes

?

NAK limit

reached

No

Yes

Error count

cleared

incremented

Error count

NAK Timeout set

Endpoint halted

Interrupt generated

?

Error

count=3

No

Error bit set

ReqPkt cleared

Error Count cleared

Interrupt generated

Yes

Implies problem
at peripheral end
of connection.

Transaction deemed

complete

Completion of either SETUP

phase or OUT data phase

No

ACK sent

RxPktRdy

set

ReqPkt cleared

Error Count cleared

Interrupt generated

ReqPkt

and StatusPkt

both set

?

Command could
not be completed

www.ti.com

USB Controller Host and Peripheral Modes Operation

For the IN Status Phase of a Control Transaction (

Figure 12

), the software driving the USB Host device

needs to:

1. Set the STATUSPKT and REQPKT bits of HOST_CSR0 (bit 6 and bit 5, respectively).
2. Wait while the controller sends an IN token and receives a response from the USB peripheral device.

Figure 12. Completion of SETUP or OUT Data Phase Flow Chart

SPRUGH3 – November 2008

Universal Serial Bus (USB) Controller

49

Submit Documentation Feedback