USB Transactions
13-77
USB Function Module
Table 13–25. Autodecoded Versus Non-Autodecoded Control Requests (Continued)
Request
Device Behavior if
Device not Configured
LH Required Action
Status
Recipient
SET_
DESCRIPTOR
All
Non-autode-
coded
The local host must stall the
command (via the Stall_Cmd
bit) if it does not support set
descriptor requests.
Command is passed to the
local host.
GET/SET
CONFIGURATION
Device
Non-autode-
coded
The local host must stall the
command (via the Stall_Cmd
bit) if configuration number is
not correct.
If the request is SET_CONFIG,
the local host must reset all
endpoints, halt endpoints not
used by the default interface
setting, set the Self_Pwr value if
device is self-powered for the
configuration set, and then set
the Dev_Cfg bit (if config nb is
not 0), or set the Clr_Cfg bit (if
config nb is 0) before allowing
status stage to complete.
The device goes to configured
state (if Dev_Cfg set), or moves
to addressed state (if Clr_Cfg
set) and a DS_Chg interrupt is
asserted to the local host.
Command is passed to the
local host.
GET/SET
INTERFACE
Interface
Non-autode-
coded
The local host must stall the
command (via the Stall_Cmd
bit) if interface/setting number is
not correct.
If the request is
SET_INTER–FACE, the local
host must reset endpoints used
by the interface, and then halt
endpoints not used by the
interface setting, before allowing
status stage to complete.
Command is passed to the
local host.
SYNCH_
FRAME
Endpoint
Non-autode-
coded
The local host must stall the
command if it does not support
SYNCH_FRAME request, else
write requested data in the
endpoint 0 FIFO.
Command is passed to the
local host.