serialmon.c

// 2010 Kenneth Finnegan
// kennethfinnegan.blogspot.com
//
// Serial monitor to print a TTL serial line
// to an HD44780 LCD screen
// Runs on any Arduino platform

#include <LiquidCrystal.h>

// initialize the library with the numbers of the interface pins
LiquidCrystal lcd(2,3,6,7,4,5);

void setup() {
  // set up the LCD's number of rows and columns: 
  lcd.begin(16, 4);
  Serial.begin(115200);
  // Print a message to the LCD to verify that it's alive.
  lcd.print("hello, world!");
}

void loop() {
  int i;
  // Scan through the four lines available on the LCD
  for (i=0; i<4; i++) {
    // busy loop until serial data is available
    while (Serial.available() < 1) { };
    // For some reason, 3rd & 4th lines require -4 cursor position
    lcd.setCursor(-4, i);
    // Clear the single line with spaces
    lcd.print ("                ");
    lcd.setCursor(-4, i);
    int j;
    // read up to 16 charaters from serial port
    // TODO: filter command codes that don't display
    //       on the HD44780 displays
    for (j=0; j < 16 && Serial.available(); j++) {
      char k = Serial.read();
      lcd.write(k);
    }
    // Pause to make reading progress easier
    delay (200);
  }
}