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+# XTMax Firmware
+
+## Prerequisites
+
+This procedure assumes a modern Windows operating system.
+
+Please follow the instructions to download and [install Teensyduino](https://www.pjrc.com/teensy/td_download.html) (which is two programs: the Arduino IDE and the Teensy board support package).
+
+## Building and deploying
+
+1) Open the Arduino IDE and load the `XTMax.ino` file.
+
+2) Under `Tools` -> `Board` select `Teensy` then `Teensy 4.1`.
+
+3) Under `Tools` -> `Optimize` select `Fastest`.
+
+4) Under `Tools` -> `CPU Speed` select `912 MHz`.
+
+5) Connect your Teensy via USB. **It is recommended that you remove the Teensy from the XTMax or remove the XTMax from the host ISA computer to avoid back-driving from USB.**
+
+6) Under `Sketch` select `Upload`.
+
+7) Put the Teensy and/or XTMax back into the host ISA compute and enjoy!
+
+## Using XTMax and its drivers
+
+See [these instructions](../../Drivers/README.md).
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