Assignment 6 – Virtual Tug-o-War Game using Direct Register Access
Connect the pushbutton switches and
LEDs to the mbed module as shown in
the schematic to the right.
The player for the red team will use the
switch connected to p14 and the player
for the green team will use the switch
connected to p27. Each player will
attempt to continuously press and release
their switch as fast as possible. The
virtual rope begins the game centered on
the playfield. Whenever a player's switch changes state (from off to on or on to off) the
virtual rope should move one unit closer to that player's side of the playfield. If the virtual
rope has been pulled close enough to the end of the playfield, the player on that end of
the playfield wins.
The virtual rope position can be in one of 7 positions as indicated by the external and
built-in LEDs (the LEDs that are on are indicated with the starbursts):
Red team has won
Rope position at the start of the game
Green team has won
Once the virtual rope has reached one of the two winning positions, the game is over and
the program should stop (go into an infinite loop). If the players want to start a new
game, they should press the mbed's reset button.
Write the program to implement this game using direct access to the microcontroller's I/O
registers instead of using the mbed's library (no #include “mbed.h”, DigitalIn, DigitalOut,
BusOut, InterruptIn, etc.). For simplicity, ignore the potential problem of switch bounce.
Submit your "main.cpp" to the appropriate dropbox on Canvas by the end of May 3rd.
p23
p24
p27
p17
p16
p14
GND Vout
Red 220 220 Green
mbed
