From 24209ae72593545ab6d7d0840b1f6a6812eee50a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ond=C5=99ej=20Hru=C5=A1ka?= <ondra@ondrovo.com>
Date: Sat, 23 Jun 2018 23:30:31 +0200
Subject: [PATCH] workaround for startup glitch

---
 display.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/display.c b/display.c
index 3fd5e15..6e59977 100644
--- a/display.c
+++ b/display.c
@@ -18,6 +18,7 @@ const uint8_t disp_digits[10] = {
 #define adc_samps_len 16
 uint8_t adc_samps[adc_samps_len];
 uint8_t adc_samp_i = 0;
+bool adc_samp_notfilled = true;
 
 #define light_sens_countdown_max 800
 uint16_t light_sens_countdown = 0;
@@ -73,6 +74,14 @@ ISR(TIMER2_OVF_vect)
 			
 			// averaging
 			adc_samps[adc_samp_i++] = brt;
+			// prefill all with the first measure to prevent the hiccup on startup
+			if (adc_samp_notfilled) {
+				adc_samp_notfilled = false;
+				for (uint8_t i = 0; i < adc_samps_len; i++) {
+					adc_samps[i] = brt;
+				}
+			}
+			
 			if (adc_samp_i == adc_samps_len) adc_samp_i = 0;
 			uint16_t sum = 0;
 			for (uint8_t i = 0; i < adc_samps_len; i++) {