diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..dbddb40
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,165 @@
+# Created by https://www.toptal.com/developers/gitignore/api/vim,python
+# Edit at https://www.toptal.com/developers/gitignore?templates=vim,python
+
+### Python ###
+# Byte-compiled / optimized / DLL files
+__pycache__/
+*.py[cod]
+*$py.class
+
+# C extensions
+*.so
+
+# Distribution / packaging
+.Python
+build/
+develop-eggs/
+dist/
+downloads/
+eggs/
+.eggs/
+lib/
+lib64/
+parts/
+sdist/
+var/
+wheels/
+pip-wheel-metadata/
+share/python-wheels/
+*.egg-info/
+.installed.cfg
+*.egg
+MANIFEST
+
+# PyInstaller
+#  Usually these files are written by a python script from a template
+#  before PyInstaller builds the exe, so as to inject date/other infos into it.
+*.manifest
+*.spec
+
+# Installer logs
+pip-log.txt
+pip-delete-this-directory.txt
+
+# Unit test / coverage reports
+htmlcov/
+.tox/
+.nox/
+.coverage
+.coverage.*
+.cache
+nosetests.xml
+coverage.xml
+*.cover
+*.py,cover
+.hypothesis/
+.pytest_cache/
+pytestdebug.log
+
+# Translations
+*.mo
+*.pot
+
+# Django stuff:
+*.log
+local_settings.py
+db.sqlite3
+db.sqlite3-journal
+
+# Flask stuff:
+instance/
+.webassets-cache
+
+# Scrapy stuff:
+.scrapy
+
+# Sphinx documentation
+docs/_build/
+doc/_build/
+
+# PyBuilder
+target/
+
+# Jupyter Notebook
+.ipynb_checkpoints
+
+# IPython
+profile_default/
+ipython_config.py
+
+# pyenv
+.python-version
+
+# pipenv
+#   According to pypa/pipenv#598, it is recommended to include Pipfile.lock in version control.
+#   However, in case of collaboration, if having platform-specific dependencies or dependencies
+#   having no cross-platform support, pipenv may install dependencies that don't work, or not
+#   install all needed dependencies.
+#Pipfile.lock
+
+# PEP 582; used by e.g. github.com/David-OConnor/pyflow
+__pypackages__/
+
+# Celery stuff
+celerybeat-schedule
+celerybeat.pid
+
+# SageMath parsed files
+*.sage.py
+
+# Environments
+.env
+.venv
+env/
+venv/
+ENV/
+env.bak/
+venv.bak/
+pythonenv*
+
+# Spyder project settings
+.spyderproject
+.spyproject
+
+# Rope project settings
+.ropeproject
+
+# mkdocs documentation
+/site
+
+# mypy
+.mypy_cache/
+.dmypy.json
+dmypy.json
+
+# Pyre type checker
+.pyre/
+
+# pytype static type analyzer
+.pytype/
+
+# profiling data
+.prof
+
+### Vim ###
+# Swap
+[._]*.s[a-v][a-z]
+!*.svg  # comment out if you don't need vector files
+[._]*.sw[a-p]
+[._]s[a-rt-v][a-z]
+[._]ss[a-gi-z]
+[._]sw[a-p]
+
+# Session
+Session.vim
+Sessionx.vim
+
+# Temporary
+.netrwhist
+*~
+# Auto-generated tag files
+tags
+# Persistent undo
+[._]*.un~
+
+# End of https://www.toptal.com/developers/gitignore/api/vim,python
diff --git a/arduino_programs/arduino_programmer/arduino_programmer.ino b/arduino_programs/arduino_programmer/arduino_programmer.ino
index 3b410b5..c10b2ed 100644
--- a/arduino_programs/arduino_programmer/arduino_programmer.ino
+++ b/arduino_programs/arduino_programmer/arduino_programmer.ino
@@ -17,6 +17,7 @@
 // Digital pins 8 to 13 correspond to PB0 to PB5
 
 byte lastOp;
+static char printBuff[128];
 
 void latchOutput() {
   static byte latchMask = 0b00010000;
@@ -52,12 +53,12 @@ void setBusMode(bool busMode) {
 
 void setAddress(int address, bool outputEnable) {
   // Position of the output enable bit withing the data to be shifted out. 
-  static byte outputEnableMask = 0x8000;
+  static int outputEnableMask = 0x8000;
   // Position of the data bit within PORTD.
   static byte dataMask = 0b00000100;
   // Position of the clock bit within PORTD.
   static byte clockMask = 0b00001000;
-
+  
   if (outputEnable) {
     // Clear output enable bit.
     address &= ~outputEnableMask;
@@ -65,10 +66,9 @@ void setAddress(int address, bool outputEnable) {
     // Set output enable bit.
     address |= outputEnableMask;
   }
-  
-  // Make sure the clock pin is low.
-  PORTD &= ~clockMask;  
 
+  // Make sure the clock pin is low.
+  PORTD &= ~clockMask;
   // Shift the data out LSB first.
   for (uint8_t i = 0; i < 16; i++, address >>= 1) {
     if (address & 1) {
@@ -148,7 +148,8 @@ void setup() {
 
   Serial.begin(9600);
   
-
+  writeEEPROM(0x1234, 0x55, true);
+  writeEEPROM(0x4321, 0x7E, true);
 }
 
 void loop() {
diff --git a/arduino_programs/arduino_tester/arduino_tester.ino b/arduino_programs/arduino_tester/arduino_tester.ino
index 9e45e71..24484da 100644
--- a/arduino_programs/arduino_tester/arduino_tester.ino
+++ b/arduino_programs/arduino_tester/arduino_tester.ino
@@ -7,8 +7,31 @@
 #define ADDRESS_0 22
 #define ADDRESS_15 50
 
-void setup() {
+#define ADDRESS_CLOCK 18
+#define WRITE_CLOCK 19
 
+void setup() {
+  Serial.begin(9600);
+  attachInterrupt(digitalPinToInterrupt(ADDRESS_CLOCK), onAddressClock, RISING);
+  attachInterrupt(digitalPinToInterrupt(WRITE_CLOCK), onWriteClock, FALLING);
+}
+
+void onAddressClock() {
+  delayMicroseconds(1);
+  Serial.print("Address: 0b");
+  Serial.print(digitalRead(OUTPUT_ENABLE));
+  for (int pin = ADDRESS_15; pin >= ADDRESS_0; pin -= 2) {
+    Serial.print(digitalRead(pin));
+  }
+  Serial.println();
+}
+
+void onWriteClock() {
+  Serial.print("Data: 0b"); 
+  for (int pin = DATA_7; pin >= DATA_0; pin--) {
+    Serial.print(digitalRead(pin));
+  }
+  Serial.println();
 }
 
 void loop() {