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LM3S5P3B Datasheet, PDF (852/1170 Pages) Texas Instruments – Stellaris® LM3S5P3B Microcontroller | |||
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Universal Serial Bus (USB) Controller
18 Universal Serial Bus (USB) Controller
18.1
The Stellaris® USB controller operates as a full-speed or low-speed function controller during
point-to-point communications with USB Host functions. The controller complies with the USB 2.0
standard, which includes SUSPEND and RESUME signaling. 32 endpoints including two hard-wired
for control transfers (one endpoint for IN and one endpoint for OUT) plus 30 endpoints defined by
firmware along with a dynamic sizable FIFO support multiple packet queueing. µDMA access to the
FIFO allows minimal interference from system software. Software-controlled connect and disconnect
allows flexibility during USB device startup.
The Stellaris USB module has the following features:
â Complies with USB-IF certification standards
â USB 2.0 full-speed (12 Mbps) and low-speed (1.5 Mbps) operation with integrated PHY
â 4 transfer types: Control, Interrupt, Bulk, and Isochronous
â 32 endpoints
â 1 dedicated control IN endpoint and 1 dedicated control OUT endpoint
â 15 configurable IN endpoints and 15 configurable OUT endpoints
â 4 KB dedicated endpoint memory: one endpoint may be defined for double-buffered 1023-byte
isochronous packet size
â Efficient transfers using Micro Direct Memory Access Controller (µDMA)
â Separate channels for transmit and receive for up to three IN endpoints and three OUT
endpoints
â Channel requests asserted when FIFO contains required amount of data
Block Diagram
Figure 18-1. USB Module Block Diagram
Endpoint Control
EP0 â 31
Control
Transmit
Receive
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
DMA
Requests
CPU Interface
Interrupt
Control
EP Reg.
Decoder
Common
Regs
Cycle
Control
Interrupts
AHB bus â
Slave mode
FIFO
Decoder
852
January 20, 2012
Texas Instruments-Production Data
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