Here is the Arduino Sketch for the IQ Keyer Project. You can program the Arduino Nano by downloading and installing the Arduino IDE and using it to compile and upload the sketch on this page.
Here are step by step instructions:
1. Install the Arduino IDE and make sure that it is closed.
2. Download and open the attached file IQ_Keyer_Sketch.zip and copy the folder CW_Keyer_IQ to your documents\ardiuno folder.
3. Download and open the attached file TimerOne-r11.zip and copy the folder TimerOne to your documents\Arduino\library folder.
4. Navigate back to documents\Arduino\CW_Keyer_IQ double click on CW_Keyer_IQ.ino.
This should bring up the Arduino IDE with the IQ keyer sketch.
5. Plug the IQKeyer into a USB port on the computer. It should enumerate as a comm port.
6. In the Arduino IDE select tools>board and select Arduino Nano.
7. Click on the right -pointing arrow and you are done.