This is a callback function for a scale change.
void scale_value_changed_for_AF_Volume( GtkWidget *scale, gpointer data ) {
int outputcount = 9;
static unsigned char command[9] = {0xfe, 0xfe, 0x80, 0xe0, 0x14, 0x01, 0x00, 0x32, 0xfd};
int value, i100, i10, i1;
value = gtk_range_get_value(GTK_RANGE (scale));
i100 = value / 100;
i10 = (value - 100*i100) / 10;
i1 = value % 10;
command[6] = i100;
command[7] = 16*i10 + i1; /* BCD coded */
write(fd, &command, outputcount);
}
And here is a main program.
adj = gtk_adjustment_new(50.0, 0.0, 256.0, 1.0, 1.0, 1.0);
scale = gtk_hscale_new(GTK_ADJUSTMENT (adj));
gtk_scale_set_value_pos(GTK_SCALE(scale), GTK_POS_TOP);
gtk_signal_connect (GTK_OBJECT (scale), "value_changed", GTK_SIGNAL_FUNC (scale_value_changed_for_AF_Volume), NULL);
label = gtk_label_new_with_mnemonic ("AF Volume");
box = gtk_vbox_new(FALSE, 0);
gtk_box_pack_start(GTK_BOX (box), scale, TRUE, TRUE, 0);
gtk_box_pack_start(GTK_BOX (box), label, TRUE, TRUE, 0);
If you change the sliders, IC-7410 will respond perfectly, and it is much less frustrating to write a code yourself than deciphering the exiting ones.