diff --git a/CMakeLists.txt b/CMakeLists.txt
new file mode 100644
index 0000000..945a7ba
--- /dev/null
+++ b/CMakeLists.txt
@@ -0,0 +1,7 @@
+cmake_minimum_required(VERSION 2.8)
+# 3rd party tools
+find_package(Qt5 COMPONENTS Widgets Qml Quick REQUIRED)
+# Directory with source code
+add_subdirectory(src)
+add_subdirectory(qt_gui)
+
diff --git a/README.md b/README.md
index 4058de3..9f30673 100644
--- a/README.md
+++ b/README.md
@@ -1,6 +1,6 @@
 # STC DIY Calculator Firmware
 
-This is a replacement firmware for the [diyleyuan calculator](http://www.diyleyuan.com/jc/L8Q.html). The calculator uses an STC IAP15W413AS microcontroller (an 8051 instruction set-compatible microcontorller) with a built in serial bootloder. This project uses SDCC to compile the C code and [stcgal](https://github.com/grigorig/stcgal) to load the new firmware.
+This is a replacement firmware for the [diyleyuan calculator](http://www.diyleyuan.com/jc/L8Q.html). The calculator is available for purchase for less than $13 shipped from eBay by searching for "diy calculator kit". The calculator uses an STC IAP15W413AS microcontroller (an 8051 instruction set-compatible microcontorller) with a built in serial bootloder. This project uses SDCC to compile the C code and [stcgal](https://github.com/grigorig/stcgal) to load the new firmware.
 
 ![calculator](./calc.jpg)
 
@@ -10,7 +10,8 @@ This is a replacement firmware for the [diyleyuan calculator](http://www.diyleyu
 	- (you must already have SDCC installed and setup so it can be found in your PATH)
 	- this will create a `main.hex` output file
 	- there is also a prebuilt binary checked in at `binaries/main.hex`
-<!-- - CMakeLists.txt is for building the Qt desktop application. -->
+- CMakeLists.txt is for building the Qt desktop application.
+	- (still a work in progress, currently doesn't do anything)
 
 # Installing
 The STC microcontroller used has a bootloader permanently stored in ROM that allows downloading new firmware over a serial port. You can re-program it using a USB-to-logic-level-serial (5V) dongle, and the stcgal program. WARNING: a lot of USB-to-logic-level-serial dongles are for 3.3V logic levels. The diyleyuan calculator runs at 5V to make it easier to power/drive the LCD display. You have a couple of options:
diff --git a/qt_gui/CMakeLists.txt b/qt_gui/CMakeLists.txt
new file mode 100644
index 0000000..c3b93ec
--- /dev/null
+++ b/qt_gui/CMakeLists.txt
@@ -0,0 +1,29 @@
+include_directories(${Qt5Widgets_INCLUDE_DIRS} ${QtQml_INCLUDE_DIRS})
+add_definitions(${Qt5Widgets_DEFINITIONS} ${QtQml_DEFINITIONS} ${${Qt5Quick_DEFINITIONS}})
+
+qt5_add_resources(QT_RESOURCES main.qrc)
+
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${Qt5Widgets_EXECUTABLE_COMPILE_FLAGS}")
+set(CMAKE_AUTOMOC ON)
+set(CMAKE_AUTORCC ON)
+set(CMAKE_AUTOUIC ON)
+set(PROJECT "RPN_Calculator")
+project(${PROJECT})
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wall -Werror -std=c++11 -fstrict-aliasing -pedantic ")
+
+if(NOT DEFINED HEADERS)
+    file(GLOB HEADERS ${CMAKE_CURRENT_SOURCE_DIR}⁄*.h)
+endif()
+# if(NOT DEFINED SOURCES)
+#     file(GLOB SOURCES ${CMAKE_CURRENT_SOURCE_DIR}⁄*.cpp)
+# endif()
+source_group("Header Files" FILES ${HEADERS})
+# source_group("Source Files" FILES ${SOURCES})
+set(SOURCES main.cpp calculator.cpp)
+add_executable(${PROJECT} ${HEADERS} ${SOURCES} ${QT_RESOURCES})
+target_link_libraries(${PROJECT}
+    Qt5::Widgets
+    Qt5::Qml
+    Qt5::Quick
+    calc
+)
diff --git a/qt_gui/calculator.cpp b/qt_gui/calculator.cpp
new file mode 100644
index 0000000..ab1d873
--- /dev/null
+++ b/qt_gui/calculator.cpp
@@ -0,0 +1,12 @@
+#include <QDebug>
+
+#include "calculator.h"
+
+Calculator::Calculator(QObject *parent) :
+	QObject(parent)
+{
+}
+
+void Calculator::buttonClicked(const QString& in) {
+	qDebug() << in;
+}
diff --git a/qt_gui/calculator.h b/qt_gui/calculator.h
new file mode 100644
index 0000000..c0eba2f
--- /dev/null
+++ b/qt_gui/calculator.h
@@ -0,0 +1,20 @@
+#ifndef QTGUI_CALCULATOR_H
+#define QTGUI_CALCULATOR_H
+
+#include <QObject>
+
+class Calculator : public QObject
+{
+	Q_OBJECT
+	
+public:
+	explicit Calculator(QObject *parent = 0);
+	
+public slots:
+	void buttonClicked(const QString& in);
+	
+};
+
+
+
+#endif //include guard
diff --git a/qt_gui/main.cpp b/qt_gui/main.cpp
new file mode 100644
index 0000000..a772de9
--- /dev/null
+++ b/qt_gui/main.cpp
@@ -0,0 +1,16 @@
+#include <QApplication>
+#include <QQmlApplicationEngine>
+#include <QQmlContext>
+#include "calculator.h"
+
+int main(int argc, char** argv)
+{
+	QApplication app(argc, argv);
+	QQmlApplicationEngine engine;
+	engine.load(QUrl(QStringLiteral("qrc:/main.qml")));
+	
+	Calculator calculator;
+	engine.rootContext()->setContextProperty("_calculator", &calculator);
+	
+	return app.exec();
+}
diff --git a/qt_gui/main.qml b/qt_gui/main.qml
new file mode 100644
index 0000000..65e79b3
--- /dev/null
+++ b/qt_gui/main.qml
@@ -0,0 +1,55 @@
+import QtQuick 2.0
+import QtQuick.Controls 1.0
+import Qt3D.Input 2.0
+
+ApplicationWindow
+{
+	visible: true
+	width:  1000
+	height: 1000
+	title: qsTr("RPN Calculator")
+	
+	//calculator
+	Column {
+		id: base;
+		spacing: 5;
+		width:  4 * (100 + 5)
+		height: 5 * (100 + 5) + 200
+		
+		//LCD
+		Rectangle {
+			id: lcd;
+			color: "gray"
+			width: 4 * (100 + 5) - 5
+			height: 200
+		}
+		
+		//Keyboard
+		Repeater {
+			model: 5;
+			//row
+			delegate: Row {
+				id: key_row;
+				spacing: 5;
+				//keys within row
+				Repeater {
+					model: 4;
+					delegate: Rectangle {
+						id: key_key;
+						width: 100;
+						height: 100;
+						color: "blue"
+						border { width: 1; color: "black" }
+						Text {
+							text: index
+							anchors.centerIn: parent
+						}
+						MouseHandler {
+							onClicked: _calculator.buttonClicked(index)
+						}
+					}
+				}
+			}
+		}
+	}
+}
diff --git a/qt_gui/main.qrc b/qt_gui/main.qrc
new file mode 100644
index 0000000..18d02bd
--- /dev/null
+++ b/qt_gui/main.qrc
@@ -0,0 +1,5 @@
+<RCC>
+	<qresource prefix="/">
+		<file>main.qml</file>
+	</qresource>
+</RCC>
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
new file mode 100644
index 0000000..cc1a7f3
--- /dev/null
+++ b/src/CMakeLists.txt
@@ -0,0 +1,4 @@
+
+add_library(decn decn/decn.c)
+
+add_library(calc main.c calc.c utils.c lcd_emulator.c key.c)
diff --git a/src/lcd_emulator.c b/src/lcd_emulator.c
new file mode 100644
index 0000000..1e8e641
--- /dev/null
+++ b/src/lcd_emulator.c
@@ -0,0 +1,93 @@
+/*
+ * lcd_emulator.c
+ *
+ *  Created on: Apr 1, 2019
+ */
+
+#include <stdio.h>
+#include <stdint.h>
+#include "lcd.h"
+
+#define CR 13 // \r
+#define TAB 9 // \n
+
+static int lcd_row, lcd_col;
+static char lcd_buf[MAX_ROWS][MAX_CHARS_PER_LINE];
+
+void LCD_Open(void){
+
+}
+
+void LCD_Clear(void){
+	lcd_row=0;
+	lcd_col=0;
+	for (int i = 0; i < MAX_ROWS; i++){
+		for (int j = 0; j < MAX_CHARS_PER_LINE; j++){
+			lcd_buf[i][j] = 0;
+		}
+	}
+}
+
+void LCD_GoTo(unsigned int row, unsigned int col){
+	if (row < MAX_ROWS && col < MAX_CHARS_PER_LINE){
+		lcd_row = row;
+		lcd_col = col;
+	} else {
+		printf("LCD_GoTo(%u, %u) out of range\n", lcd_row, lcd_col);
+	}
+}
+
+static void to_row(unsigned char row_to){
+	if (row_to == 0){
+		lcd_row = 0;
+	} else {
+		lcd_row = 1;
+	}
+	lcd_col = 0;
+}
+
+void LCD_OutString(const char *string, uint8_t max_chars) {
+	const char *s;
+	for (s = string; *s && max_chars > 0; s++, max_chars--) {
+		TERMIO_PutChar(*s);
+	}
+}
+
+short TERMIO_PutChar(unsigned char letter) {
+	if (letter == CR || letter == '\n') {
+		LCD_Clear();
+	} else if (letter == TAB || letter == '\t') {
+		if (lcd_row == 0) {
+			to_row(1);
+		} else {
+			to_row(0);
+		}
+	} else {
+		lcd_buf[lcd_row][lcd_col] = letter;
+		lcd_col++;
+		if (lcd_col > MAX_CHARS_PER_LINE) {
+			if (lcd_row == 0) {
+				to_row(1);
+			} else {
+				to_row(0);
+			}
+		}
+	}
+
+	return 1;
+}
+
+void LCD_ClearToEnd(uint8_t curr_row){
+	while (lcd_col != 0 && lcd_row == curr_row){
+		TERMIO_PutChar(' ');
+	}
+}
+
+void LCD_OutNibble(uint8_t x){
+	x &= 0xf; //ensure only bottom nibble
+	if (x <= 9){
+		TERMIO_PutChar(x + '0');
+	} else {
+		TERMIO_PutChar(x - 10 + 'a');
+	}
+}