LM3S3748 Datasheet, PDF (503/753 Pages) List of Unclassifed Manufacturers – Microcontroller

LM3S3748 Microcontroller
17
17.1
Univeral Serial Bus (USB) Controller
The Stellaris^® USB controller operates as a function controller for a full-speed or low-speed host or
device in point-to-point or multipoint (hub) communications with USB functions. The controller
complies with the USB 2.0 standard, which includes suspend and resume signaling. Three
configurable endpoints (1-3) with a dynamic sizable FIFO support multiple packet queueing. DMA
access to the FIFO allows minimal interference from system software. The controller has the capability
to access an external power regulator through a power enable pad output (USB0EPEN) and power
fault detect pad input (USB0PFLT).
The Stellaris^® USB module has the following features:
■ Standards-based
■ USB 2.0 full-speed (12 Mbps) and low-speed (1.5 Mbps) operation
■ USB Host mode
■ Integrated PHY
■ 4 transfer types: control, interrupt, bulk, and isochronous
■ 1 dedicated bi-directional control endpoint
■ 3 receive and 3 transmit configurable endpoints
■ 4 KB dedicated endpoint memory
– Direct Memory Access
– One endpoint may be defined for double-buffered 1023-byte isochronous packet size
Block Diagram
Figure 17-1. USB Module Block Diagram
Endpoint Control
EP0 – 3
Control
Transmit
Receive
Combine
Endpoints
Host
Transaction
Scheduler
USB PHY
USB Data Lines
D+ and D-
USB FS/LS
PHY
UTM
Synchronization
Data Sync
Timers
Packet
Encode/Decode
Packet Encode
Packet Decode
CRC Gen/Check
FIFO RAM
Controller
Rx
Rx
Buff
Buff
Tx
Tx
Buff
Buff
Cycle Control
CPU Interface
Interrupt
Control
EP Reg.
Decoder
Common
Regs
Cycle
Control
FIFO
Decoder
DMA
Requests
Interrupts
AHB bus –
Slave mode
April 08, 2008
503
Preliminary