Arduino uno User Manual

if (z_button) {
-
init_game();
20
state = RUNNING;
-
}
-
}
-
-
void game_over() {
25
tv.clear_screen();
-
tv.select_font(font8x8);
-
tv.printPGM(28, 38, PSTR("Game Over"));
-
int x = (WIDTH - 7 * 8) / 2;
-
if (hits > 9)
30
x = (WIDTH - 8 * 8) / 2;
-
tv.printPGM(x, 50, PSTR("Hits: "));
-
tv.print(x + 6 * 8, 50, hits);
-
if (z_button) {
-
state = STARTING;
35
z_button = false;
-
delay(200);
-
}
-
}
-
40
void update_game() {
-
tv.clear_screen();
-
tv.draw_circle(target_x, target_y, target_r, WHITE);
-
move_crosshairs();
-
draw_crosshairs();
45
check_target();
-
if (target_count == MAX_TARGET + 1) {
-
state = DONE;
-
z_button = false;
-
delay(200);
50
}
-
}
-
The intro , start_game , and game_over functions are very similar. They print a
message to the screen, then they wait for a Z button press. If the Z button
was pressed, they move to the next state. Before they move to the next state,
they set z_button to false and wait for 200 milliseconds. This is necessary to
debounce the Z button.
All three functions use yet another TVout method. Look at line 3, for example.
Here we use TVout’s printPGM method. It works like the regular print method,
but it reads the string to be output from the Arduino’s flash memory and not
from its precious SRAM. For applications that display a lot of constant mes-
sages, this can save a lot of memory.
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Arduino uno Specifications

General

Form factor	Arduino
Certification	RoHS, FC, CE
Processor model	-
Processor frequency	- MHz
Microcontroller model	ATmega328
Microcontroller frequency	16 MHz
DC input voltage	7-12 V
Operating voltage	5 V
DC current per I/O pin	40 mA
Flash memory	0.032 MB
Maximum internal memory	- GB
SRAM (Static Random Access Memory)	2 KB
EEPROM (Electrically Erasable Programmable Read-Only Memory)	1 KB
Wi-Fi	No
Number of analog I/O pins	6
Number of digital I/O pins	14

Weight and Dimensions

Board dimensions	53.4 x 68.6 mm