From a51d525b75ead2c23ef83795d8ff60b76796d72c Mon Sep 17 00:00:00 2001
From: gregor herrmann <gregor@toastfreeware.priv.at>
Date: Wed, 28 Oct 2020 16:35:14 +0100
Subject: [PATCH] warn during warmup

output a warning '(W)' after the co2 value during the first minute,
if the value is -1 or 410 which seems to happen each time after powering the
board on for a couple of measurements.
---
 airingbutler.ino | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/airingbutler.ino b/airingbutler.ino
index 075db34..a446855 100644
--- a/airingbutler.ino
+++ b/airingbutler.ino
@@ -18,6 +18,7 @@ MHZ19 mhz19 = MHZ19(rx_pin,tx_pin);
 LiquidCrystal lcd(7, 8, 9, 10, 11, 12);
 
 unsigned long time;
+unsigned long warmuptime = 60000; // 1 min.
 int co2 = 0;
 int temp = 0;
 int lastppm = 0;
@@ -96,6 +97,9 @@ void loop()
 	lcd.setCursor(0, 0);
 	lcd.print("CO2: ");
 	lcd.print(co2);
+	if (time < warmuptime && (co2 == -1 || co2 == 410)) {
+		lcd.print (" (W)");
+	}
 	lcd.print(" ppm    ");
 	lcd.setCursor(0, 1);
 	lcd.print("Temp: ");
-- 
2.39.5