The USBToTTL series of converter boards are tiny 1" by 1.5" boards which translate USB 1.1 and 2.0 data to TTL-serial levels which are compatible with all of our RS232 and TTL-Serial motor controller products; they therefore allow any of those controllers to communicate via USB with a host computer. They are available in two models; one just provides the serial communications, while the other adds a switched 5 volt tap from the USB power (up to 400 mA draw, off when the computer is asleep). These two new upgrades to our original USBToTTL board both have limited ESD protection available, once they have been connected to a properly grounded USB connection.
(The picture on the left is the AR-USBToTTL-L rev 06 board, while the one on the right is the AR-USBToTTLEU-L board which supports access to the USB 5 volt power).
The boards are designed such that you can use #4 mounting posts to mount them in your system, or you may panel-mount them using right-angle 1/4" brackets. In the latter case, you can direct the USB-B connector out through your panel, thus providing you with a convenient external connection.
The chip used as the converter chip is the FTDI (www.ftdichip.com) FT232RL, and the plug-and-play drivers are those provided by FTDI for use under Windowstm, Linux, and MacOS. These drivers include USB-To-COM port emulators, so that the USBToTTL board acts like a new "COM" port on your system.
Our complete manual describing the product is available here.
This series of boards permit communication between a USB-based computer and any TTL-serial compliant device, such as the Parallax Basic or Javalin Stamp (www.parallax.com). Although we most commonly use it at a communications rate of 9600 baud (when operated with our products), it actually supports baud rates up to 3 megabaud when used with other TTL-serial compatible devices. Note that the phrase "TTL-Serial" implies "normal" RS232-serial semantics; that is to say, each "byte" of data will have at least one start bit and at least one stop bit, in addition to the appropriate data bits (as configured in your 'Com Port' settings under Linux, MacOS, or Windowstm).
The USBToTTLEU board adds a switched tap into the USB 5 volt power. This tap is provided via a mosfet switch, which turns off the 5 volts at any time that the computer goes into a "sleep" or "hibernation" mode of operation, so as to avoid draining the battery on laptops (and to obey USB specifications). Up to 400 mA of power may be available, depending on the USB connection (for example, unpowered hubs may have far less power available).
These boards are compatible with any of our motor controllers that support TTL-Serial communication. At present, only the SD4DP high-performance USB-based step-and-direction product is unable to be connected to your computer using the USBToTTL serial converter. All of our other products may be paired with the USBToTTL converter board, if this simplifies your mounting considerations.
Please note that you need to provide your own USB cable (standard A-B pair) of the correct length for your application.