AT91SAM7S128 Datasheet, PDF (409/495 Pages) ATMEL Corporation – THUMB BASED MICROCONTROLLERS

AT91SAM7S128 Preliminary
33. USB Device Port (UDP)
33.1 Description
The USB Device Port (UDP) is compliant with the Universal Serial Bus (USB) V2.0 full-speed
device specification.
Each endpoint can be configured in one of several USB transfer types. It can be associated with
one or two banks of a dual-port RAM used to store the current data payload. If two banks are
used, one DPR bank is read or written by the processor, while the other is read or written by the
USB device peripheral. This feature is mandatory for isochronous endpoints. Thus the device
maintains the maximum bandwidth (1M bytes/s) by working with endpoints with two banks of
DPR.
Table 33-1.
Endpoint
Number
0
1
3
3
USB Endpoint Description
Mnemonic
EP0
EP1
EP2
EP3
Dual-Bank
No
Yes
Yes
No
Max. Endpoint Size
8
64
64
64
Endpoint Type
Control/Bulk/Interrupt
Bulk/Iso/Interrupt
Bulk/Iso/Interrupt
Control/Bulk/Interrupt
Suspend and resume are automatically detected by the USB device, which notifies the proces-
sor by raising an interrupt. Depending on the product, an external signal can be used to send a
wake-up to the USB host controller.
6116A–ATARM–15-Apr-05
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