Not recommended for new desigs. Replacement product: LinkUSBi-M.
The LinkUSBi is an advanced, intelligent USB 2.0 full speed interface for use with Dallas Semiconductor 1-Wire and iButton components. It uses superior digital and analog methods to accomplish more-reliable operation on a wide variety of network topologies. It also offers many functions that simplify network communications and some diagnostic tools as well.
The LinkUSBi has been designed to operate reliably on long and short 1-Wire busses. It has a special analog interface design that uses matched impedances and slew rate controls, as well as smart cable pre-charge. In addition, the firmware (programming) is adaptive and makes adjustments for a variety of network parameters automatically.
The LinkUSBi is based on The Link, which was designed in cooperation with Dallas Semiconductor Corp., Dallas, Texas, manufacturer of 1-Wire and iButton devices and various accessories. Some terms used in this document may be trademarks of Dallas Semiconductor Corporation, and are used with their permission. Application note 244 from the Maxim-Dallas web site describes the improvements implemented by the LinkUSBi in greater detail.
USB to Serial Bridge
The LinkUSBi is based on the proven iButtonLink Link45 product, with an FTDI FT232R USB UART chip bridging the USB to the internal microprocessor's serial port. The FT232R is USB 2.0 Full Speed compatible. Drivers should already be present in recent Windows versions. The latest driver versions for Windows, Linux and Macintosh may be downloaded from http://www.ftdichip.com/.
The FTDI driver creates a virtual COM port on the host computer to communicate with the LinkUSBi. If you change the virtual COM port baud rate it changes the baud rate in the FT232R chip that connects to the LinkUSBi microprocessor. This will make the LinkUSBi appear unresponsive until the baud rate is returned to its previous setting. The proper sequence to enable higher baud rates is to first change the LinkUSBi baud rate first the ASCII '^', '`', or ',' commands, then change the virtual COM port speed.
