User's Manual

Bluegiga Technologies Oy
Page 25 of 52
13 Serial Interfaces
13.1 USB Interface
BT111 has a full-speed (12Mbps) USB interface for communicating with other compatible digital devices. The
USB interface on BT111 acts as a USB peripheral, responding to requests from a master host controller.
BT111 supports the Universal Serial Bus Specification, Revision v2.0 (USB v2.0 Specification) and USB
Battery Charging Specification, available from http://www.usb.org. For more information on how to integrate
the USB interface on BT111 see the WTxx / BTxxx USB Design Guide.
As well as describing USB basics and architecture, the application note describes:
 Power distribution for high and low bus-powered configurations
 Power distribution for self-powered configuration, which includes USB VBUS monitoring
 USB enumeration
 Electrical design guidelines for the power supply and data lines, as well as PCB tracks and the effects
of ferrite beads
 USB suspend modes and Bluetooth low-power modes:
 Global suspend
 Selective suspend, includes remote wake
 Wake on Bluetooth, includes permitted devices and set-up prior to selective suspend
 Suspend mode current draw
 PIO status in suspend mode
 Resume, detach and wake PIOs
 Battery charging from USB, which describes dead battery provision, charge currents, charging in
suspend
Modes and USB VBUS voltage consideration
 USB termination when interface is not in use
 Internal modules, certification and non-specification compliant operation
See chapter 17 for the default USB vendor and product ID settings.
13.2 Programming and Debug Interface
This SPI programming and debug interface can configure the PS Keys stored in the internal EEPROM and
can also debug BT111. Bluegiga provides the development and production tools to communicate over this
interface from a PC.
BT111 uses a 16-bit data and 16-bit address programming and debug interface. Transactions occur when the
internal processor is running or is stopped. Data is written or read one word at a time, or the auto-increment
feature is available for the block access.
Configuring the parameters of the BT111 and running test scripts is also possible via the USB interface with
certain limitations; please see Section 14 for more information.