Connect to Robots
Modern browsers are amazing; as you already have seen, you can create serious apps that run entirely in a browser. There is just this big difference; due to security concerns, browser apps like Logo cannot access all of the hosting computer’s resources. This is especially true for file access, which you already learned in the chapter about files.
Unfortunately, there is more: Logo is also banned from accessing some devices like serial ports. This means that the Web version of Logo cannot control your Pro-Bot. Note that the desktop version is not affected.
Android devices, Chromebooks and Macs support Bluetooth connectivity out of the box. Logo supports the new Web Bluetooth technology. This technology is available on most platforms, or on other browsers than Chrome. For Windows, you need the latest build (70) of the Chrome browser and a recent version of Windows 10. iOS devices, unfortunately, do not offer Bluetooth connectivity.
If you have not installed the Google Chrome browser, now is the time. You can download the Chrome installer from here.
Connect to Pro-Bot or USB-based robots
The desktop version of Logo comes with built-in drivers to access your computer’s hardware. Usually, you just plug in your Pro-Bot, and you are ready to go. The PROBOT? command reports TRUE if Logo found a connected Pro-Bot. Make sure that a Pro-Bot is turned on, and that its USB cable is connected to the computer.
The Web version cannot connect to Pro-Bot. If you try, Logo displays a dialog and recommends you to use the desktop version.
Select a Bluetooth Robot
Bluetooth is a special radio built in to most computers nowadays. You have probably already used Bluetooth to connect your smartphone to a headset, or if you drive a car, to connect your smartphone to your car. If your computer does not have a Bluetooth radio, you can buy a mini Bluetooth dongle for around $10.
Please select “Connect to Bluetooth Device…” from the Tools menu. If your browser supports Web Bluetooth, it displays a selection dialog that is populated over time with Logo-compatible the Bluetooth devices that the browser found. Select the device that you’d like to connect to. A Blue-Bot should, for example, turn blue, and an InO-Bot should beep and flash its lights.
Again, make sure that your robots are turned on!
If you connect to a Blue-Bot, the Blue-Bot commands will be available. Please see the Robots page for more information about Logo robot commands.
If you connect to an InO-Bot or a Root robot, Logo creates a special turtle that looks like that robot, and that is connected to your robot. Logo also sets the TELL list to that turtle so you can start issuing commands like FORWARD or RIGHT right away, and both the screen turtle and the robot will move! To disconnect, ERASE your turtle.
See the chapter about floor robots for more information.
On some computers, it is difficult to connect to a robot. If you experience problems, try the following:
- Make sure that you have paired your robot with your computer. Also make sure that your robot has been paired as a headset device. This sounds strange, but your robot disguises itself as a headset device.
- Turn Bluetooth off and on again.
- Go to the Bluetooth Settings dialog of your operating system, remove the robot, and try to re-pair.
- Make sure that your robot is not too close to a USB 3 device; USB 3 may emit pulses that could disrupt Bluetooth transmissions.