Data Sheet

24
FORM NO.: FR2-015_ A Responsible Department：WBU Expiry Date: Forever
The information contained herein is the exclusive property of AzureWave and shall not be distributed, reproduced, or disclosed
in whole or in part without prior written permission of AzureWave.
3.4.3.1. USB 2.0 Device Interface Description
Table shows the signal mapping between the AW-CM276NF and the USB Specification, Revision 2.0.
3.4.3.2. USB 2.0 Device Functional Description
The device controller uses internal Scatter/Gather DMA engine to transfer the transmit packet from
internal SRAM to USB and the receive packet from USB to internal SRAM. The Device IN Endpoint
DMA (DIEPDMAn) and Device OUT Endpoint DMA (DOEPDMAn) registers are used by the DMA
engine to access the base descriptor. The application is interrupted after the programmed transfer
size extracted from the descriptors is transmitted or received. By using registers, interrupts, and
special data structures, the device controller can communicate with the device controller driver
(application/software) about bus states, host request, and data transfer status. The device controller
driver also has all of the routines to respond to the device framework commands issued by a USB
host, so it controls the attachment, configuration, operation, and detachment of the device.
3.4.4. High-Speed UART Interface
The AW-CM276NF supports a high-speed Universal Asynchronous Receiver/Transmitter (UART)
interface, compliant to the industry standard 16550 specification. High-speed baud rates are
supported to provide the physical transport between the device and the host for exchanging
Bluetooth data. Table shows the rates supported.
The UART interface features include:
FIFO mode permanently selected for transmit and receive operations
Two pins for transmit and receive operations