In order to program with GTK+3, we have to install it on our PC, read last post "Install GTK+3 and compile with gcc in Linux". For the USB Serial communication part, refer to the post "Serial communication between Arduino and PC using C with termios".
Here is the code combine the termios and GTK+3 GtkColorChooser to build GUI for user to choice color, and send to Arduino Esplora via USB serial.
GtkEsploraColor.c:
#include <gtk/gtk.h>
#include <string.h>
#include <fcntl.h>
#include <termios.h>
int tty_fd;
struct termios old_stdio;
static void
chooser_color_activated(GtkColorChooser *chooser,
GdkRGBA *color, gpointer user_data)
{
GtkWidget *window = user_data;
int intR = (int)((color->red)*65535);
int intG = (int)((color->green)*65535);
int intB = (int)((color->blue)*65535);
GdkColor gColor = {
0,
intR,
intG,
intB};
gtk_widget_modify_bg(GTK_WIDGET(window), GTK_STATE_NORMAL, &gColor);
char bytes[] = {
(char)(intB>>8),
(char)(intG>>8),
(char)(intR>>8)};
write(tty_fd, bytes, 3);
}
void destroy( GtkWidget *widget,
gpointer data )
{
close(tty_fd);
tcsetattr(STDOUT_FILENO,TCSANOW,&old_stdio);
g_print ("Bye!\n");
gtk_main_quit();
}
int main( int argc, char *argv[])
{
//Prepare for termios
struct termios tio;
struct termios stdio;
//struct termios old_stdio;
//int tty_fd;
unsigned char c='D';
tcgetattr(STDOUT_FILENO,&old_stdio);
printf("Please start with %s /dev/ttyACM0 (for example)\n",argv[0]);
memset(&stdio,0,sizeof(stdio));
stdio.c_iflag=0;
stdio.c_oflag=0;
stdio.c_cflag=0;
stdio.c_lflag=0;
stdio.c_cc[VMIN]=1;
stdio.c_cc[VTIME]=0;
tcsetattr(STDOUT_FILENO,TCSANOW,&stdio);
tcsetattr(STDOUT_FILENO,TCSAFLUSH,&stdio);
fcntl(STDIN_FILENO, F_SETFL, O_NONBLOCK); // make the reads non-blocking
memset(&tio,0,sizeof(tio));
tio.c_iflag=0;
tio.c_oflag=0;
tio.c_cflag=CS8|CREAD|CLOCAL; // 8n1, see termios.h for more information
tio.c_lflag=0;
tio.c_cc[VMIN]=1;
tio.c_cc[VTIME]=5;
tty_fd=open(argv[1], O_RDWR | O_NONBLOCK);
cfsetospeed(&tio,B9600); // 9600 baud
cfsetispeed(&tio,B9600); // 9600 baud
tcsetattr(tty_fd,TCSANOW,&tio);
//---
GtkWidget *window;
GtkWidget *box;
GtkWidget *label;
GtkWidget *chooser;
gtk_init(&argc, &argv);
window = gtk_window_new(GTK_WINDOW_TOPLEVEL);
gtk_window_set_default_size(GTK_WINDOW(window), 400, 250);
gtk_window_set_title(GTK_WINDOW(window), "arduino-er.blogspot.com");
box = gtk_box_new(GTK_ORIENTATION_VERTICAL, 5);
label = gtk_label_new("GtkColorChooser to Arduino Esplora");
gtk_box_pack_start(GTK_BOX(box), label, FALSE, FALSE, 3);
//Create GtkColorChooser
chooser = gtk_color_chooser_widget_new();
gtk_box_pack_start(GTK_BOX(box), chooser, FALSE, FALSE, 3);
g_signal_connect (GTK_COLOR_CHOOSER(chooser),
"color-activated",
G_CALLBACK (chooser_color_activated),
window);
g_signal_connect(G_OBJECT(window), "destroy",
G_CALLBACK(destroy), NULL);
gtk_container_add(GTK_CONTAINER(window), box);
gtk_widget_show_all(window);
gtk_main();
return 0;
}
Compile it with command:
$ gcc GtkEsploraColor.c -o GtkEsploraColor `pkg-config --cflags --libs gtk+-3.0`
Arduino Esplora code, SerialColor.ino:
It's same as in the post "Serial communication between Arduino Esplora and PC")
#include <Esplora.h>
#include <TFT.h>
#include <SPI.h>
void setup() {
EsploraTFT.begin();
EsploraTFT.background(0,0,0);
EsploraTFT.stroke(255,255,255); //preset stroke color
//Setup Serial Port with baud rate of 9600
Serial.begin(9600);
//indicate start
Esplora.writeRGB(255, 255, 255);
delay(250);
Esplora.writeRGB(0, 0, 0);
}
void loop() {
if(Serial.available()){
char bytesIn[3] = {0x00, 0x00, 0x00};
int i = 0;
while(Serial.available()){
bytesIn[i] = Serial.read();
i++;
if(i==3)
break;
}
EsploraTFT.background(bytesIn[0], bytesIn[1], bytesIn[2]);
Esplora.writeRGB(bytesIn[0], bytesIn[1], bytesIn[2]);
}
}
Before run GtkEsploraColor, determine the connect USB port with dmesg:
- Insert Arduino Esploar to USB port
- Enter the command to check the port
$ dmesg
- The attached port should be listed in last lines. It's ttyACM0 in my setup
- Enter the command to run:
$ ./GtkEsploraColor /dev/ttyACM0
- Double Click on the color buttons to set color. The LCD screen and LED on Arduino Esplora should be changed accordingly.
