Bought an LCD display and keyboard this week, so had a go at hooking them up this afternoon. The display is connected to an I2C bus and also reads the keys pressed on a keypad.
Here is the script that I have used - it is just a quick check that everything works. At the moment I'm not sure what I'll use it for but need to sort out some better cables, mine were a bit cobbled together.
#include <bv4618_I.h>
#include <Wire.h>
BV4618_I di(0x31,9); // 0x62 I2C address (8 bit)
void setup()
{
}
void loop()
{
const char kb[]={0xee,0xde,0xbe,0x7e,0xed,0xdd,0xbd,0x7d,0xeb,0xdb,0xbb,0x7b,0xe7,0xd7,0xb7,0x77};
char tmp;
// set up display geometry
di.setdisplay(4,20);
// set up keyboard scan codes, alter the above constant array
// this will depend on how the keypad has been wired
di.setkeycodes(kb);
// clear screen
di.cls();
di.puts("Display Test");
di.rowcol(2,1);
di.backlight(1);
// This requires a wire from the INT pin of the BV4618 to pin
// D9 on the Ardino. The pin is specified in the constructor
// while(1) {
// if(!di.keyint()) {
// tmp=di.key();
// if(tmp > 9) tmp+='A'-10;
// else tmp+='0';
// di.putch(tmp);
// di.putch(' ');
// }
// }
// This does not require a wire as it poles keys for a value
// other then 0. di.keys returns the number of keys in the
// buffer
while(1) { // do forever
if(di.keys()) {
tmp=di.key();
// Take the position in the array and convert it into the key that is pressed.
if(tmp < 3) tmp+=49;
else if (tmp == 3) tmp+=62;
else if (tmp < 7) tmp+=48;
else if (tmp == 7) tmp+=59;
else if (tmp < 11) tmp+=47;
else if (tmp == 11) tmp+=56;
else if (tmp == 12) {
tmp+=30;
di.backlight(0); // Just messing
}
else if (tmp == 13) tmp+=35;
else if (tmp == 14) { //# Key moves down a line
tmp+=21;
di.crdown();
di.backlight(1);
}
else if (tmp == 15) tmp+=53;
di.putch(tmp);
di.putch(' ');
// a delay releases bus - no keys will be lost as the BV4218
// will capture every keypress for when the cpu comes back
delay(500);
}
}
}
It's really just a variation of the example file provided.
