BCM89359 Advance Data Sheet
USB Interface
USB Interface
Features
The following USB interface features are supported:
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USB Protocol, Revision 2.0, full-speed (12 Mbps) compliant
Optional composite device with up to three functions internal to the device
Global and selective suspend and resume with remote wakeup
Link power management L1 state with remote wakeup
HID, DFU, UHE (proprietary method to emulate an HID device at system bootup)
Integrated detach resistor
Operation
The BCM89359 can be configured to boot up as either a single USB peripheral or USB composite device with
multiple interfaces. As a single peripheral, the host detects a single USB Bluetooth device. In hub mode, the
host detects a hub with one to three of the ports already connected to USB devices (see Figure 16).
Figure 16: USB Composite Device Configuration
Host
USB Composite Device
Peripheral
USB Interface 0
HID Keyboard
USB Interface 1
HID Mouse
USB Interface 2, 3, 4
Bluetooth
Depending on the desired composite device configuration, the BCM89359 can boot up showing the three
functions of logical USB devices internal to the BCM89359: a generic Bluetooth device, a mouse, and a
keyboard. In this mode, the mouse and keyboard are emulated functions, since they connect to real HID devices
via a Bluetooth link. The Bluetooth link to these HID functions is hidden from the USB host. To the host, the host,
the mouse, and/or keyboard appear to be directly connected to the USB port. This Broadcom proprietary
architecture is called USB HID Emulation (UHE).
The USB device, configuration, and string descriptors are fully programmable, allowing manufacturers to
customize the descriptors, including vendor and product IDs, the BCM89359 uses to identify itself on the USB
port. To make custom USB descriptor information available at boot time, stored it in external NVRAM.
Broadcom®
September 9, 2014 • 89359-DS100-R
Page 48
BROADCOM CONFIDENTIAL
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