add readme, delete old license

LICENSE

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-The MIT License (MIT)
-
-Copyright (c) 2016 Ondřej Hruška
-
-Permission is hereby granted, free of charge, to any person obtaining a copy
-of this software and associated documentation files (the "Software"), to deal
-in the Software without restriction, including without limitation the rights
-to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-copies of the Software, and to permit persons to whom the Software is
-furnished to do so, subject to the following conditions:
-
-The above copyright notice and this permission notice shall be included in all
-copies or substantial portions of the Software.
-
-THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
-SOFTWARE.

README.md

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+# 1-Wire tester
+
+Uses Arduino Pro Mini, Arduino Nano or similar, with ATmega328P.
+
+LCD is HD44780, 2-line.
+
+## Pinout
+
+- D2 - RS
+- D3 - RW
+- D4 - E
+- D5..D8 - DATA4..7
+- D9 - 1-Wire data, 4k7 pullup to 5V
+
+## Usage
+
+Everything is automatic, just connect 1-Wire devices to the data pin.
+ 
+ROM code reading works in parasitic mode, but temperature measurement 
+is implemented only in 3-wire mode.