From 89d855627d6517f03f63cfb43bbe7e9882c2b860 Mon Sep 17 00:00:00 2001
From: Wolfgang Hottgenroth <wolfgang.hottgenroth@icloud.com>
Date: Fri, 14 Aug 2020 19:55:40 +0200
Subject: [PATCH] some more documentation

---
 main.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/main.c b/main.c
index d6a8e97..63bc299 100644
--- a/main.c
+++ b/main.c
@@ -36,6 +36,8 @@
 #define COMM_ENABLE_BIT BIT4
 #define COMM_RESULT_BIT BIT2
 
+// derived from the calculation in mbus-converter.ods
+// assumes a 25Ohm shunt resistor and a 10mA swing
 #define SPACE_MARK_THRESHOLD 100