From d23207fcfee9b1479da8cfa085719f860b5f8360 Mon Sep 17 00:00:00 2001
From: Pavel Machek <pavel@ucw.cz>
Date: Sun, 24 Nov 2024 13:04:50 +0100
Subject: [PATCH] skyspy: notes for more development

---
 apps/skyspy/skyspy.app.js | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/apps/skyspy/skyspy.app.js b/apps/skyspy/skyspy.app.js
index 16e18a481..a3e1c8a33 100644
--- a/apps/skyspy/skyspy.app.js
+++ b/apps/skyspy/skyspy.app.js
@@ -1,5 +1,21 @@
 /* Sky spy */
 
+/*
+   Four phases of GPS acquision:
+
+   search for sky -- not enough sattelites
+   wait for signal -- have 5 sattelites with good SNR
+   2D fix
+   3D fix
+
+   How to tell good signal
+   # satelites
+   hdop
+   diff to barometer altitude
+   variations in diff to barometer altitude
+
+*/
+
 /* fmt library v0.2.3 */
 let fmt = {
   icon_alt : "\0\x08\x1a\1\x00\x00\x00\x20\x30\x78\x7C\xFE\xFF\x00\xC3\xE7\xFF\xDB\xC3\xC3\xC3\xC3\x00\x00\x00\x00\x00\x00\x00\x00",