NEX ROBOTICS FIREBIRD V ATMEGA 2560 Hardware Manual page 96

6. PC Based Control Using Serial Communication
In this chapter, simple robot control over wired (USB / serial) or wireless medium (XBee
wireless module) is covered. User can expand this protocol further to write his own applications.
Using good packet based protocol, user can design applications involving complex multi robot
communication scheme with robots to robots and robots to PCs simultaneous communication. A
more bit advanced communication protocol for the robot control and sensor data acquisition is
covered in the chapter 7.
6.1: Communication protocol for simple robot control
Table 6.1: Control commands for the simple robot control protocol
Table 6.1 shows the simple robot control protocol. Using this, robot can be moved in forward,
backward, left or right directions and its buzzer can be turned on or off. You can use any serial
port control software such as hyper terminal or terminal.exe etc. For user friendliness keys of the
numerical pad of standard 104 keys "querty" keyboards are used. When a particular number key
is pressed, its ASCII character value is transmitted over serial / USB port. Robot receives this
ASCII values and based on its value it actuates its motors, buzzer etc. Keys are mapped in the
intuitive way on the Numerical pad of the keyboard.
This communication protocol is covered in the following experiments which are located in the
"Experiments" folder in the documentation CD. All these experiments are exactly same only
UART port number is different.
1. 13A_Serial_Communication: Serial communication via RS232 serial port.
2. 13B_Serial_Communication_USB-RS232: Serial communication via onboard FT232
USB to Serial Converter
3. 13C_Serial_Communication_ZigBee_wireless: Serial communication via XBee wireless
module (if installed).
Section 6.2 and 6.3 covers robot control using PC's USB port and XBee wireless module.
Important:
While using "Numerical Pad" of the key board, make sure that "Num Lock" is on.
© NEX Robotics Pvt. Ltd. and ERTS Lab, CSE, IIT Bombay, INDIA
Character ASCII value
8 0x38
2 0x32
4 0x34
6 0x36
5 0x35
7 0x37
9 0x39
Fire Bird V ATMEGA2560 Hardware Manual
Action
Forward
Backward
Left
Right
Stop
Buzzer On
Buzzer Off
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