User's Manual

USB compliant and can bear the USB logo. Such qualification can be obtained from a USB

plug fest or from an independent USB test house.

Terminals USB_DP and USB_DN adhere to the USB specification 2.0 (Chapter 7) electrical

requirements.

9.2.10 USB 2.0 Compatibility

WT12 is compatible with USB v2.0 host controllers; under these circumstances the two

ends agree the mutually acceptable rate of 12Mbits/s according to the USB v2.0

specification.

9.3 SPI Interface

The synchronous serial port interface (SPI) for interfacing with other digital devices. The

SPI port can be used for system debugging. It can also be used for programming the Flash

memory. SPI interface is connected using the MOSI, MISO, CSB and CLK pins.

9.4 I/O Parallel Ports

The Parallel Input Output (PIO) Port is a general-purpose I/O interface to WT12. The port

consists of six programmable, bi-directional I/O lines, PIO[2:7].

Programmable I/O lines can be accessed either via an embedded application running on

WT12 or via private channel or manufacturer-specific HCI commands.

All PIO lines are configured as inputs with weak pull downs at reset.

PIO[2] / USB_PULL_UP (1)

This is a multifunction terminal. The function depends on whether WT12 is a USB or UART

capable version. On UART versions, this terminal is a programmable I/O. On USB versions,

it can drive a pull-up resistor on USB_D+. For application using external RAM this terminal

may be programmed for chip select.

PIO[3] / USB_WAKE_UP (1)

This is a multifunction terminal. On UART versions of WT12 this terminal is a

programmable I/O. On USB versions, its function is selected by setting the Persistent

Store Key PSKEY_USB_PIO_WAKEUP (0x2cf) either as a programmable I/O or as a

USB_WAKE_UP function.

PIO[4] / USB_ON (1)

This is a multifunction terminal. On UART versions of WT12 this terminal is a

programmable I/O. On USB versions, the USB_ON function is also selectable.

PIO[5] / USB_DETACH (1)

This is a multifunction terminal. On UART versions of WT12 this terminal is a

programmable I/O. On USB versions, the USB_DETACH function is also selectable.