Start • Simple Video Signal • Video with the LPC2138 • Video Algorithm • Tricks Used • Vertical Sync & Resolution • Video for other Apps • Oscilloscope • Implementation • Construction & Results • Generate Video • Sources and PDF

There are many low-cost solutions (e.g., sound card-based) based on USB stand-alone devices that will turn your PC into a digital storage oscilloscope (DSO). All of them have a significant disadvantage: when you use the PC for a measurement and other functions at the same time, you must click your mouse again and again to switch between applications. Of course, you may use a dedicated notebook, but the other disadvantages will remain.

You could also use your old TV with a special add-on tool. Advanced microcontrollers have all the parts (e.g., ADC and RAM) for implementing such a tool with a single chip. I’ll describe a similar device in this article. My TV-based oscilloscope is built around a Keil MCB2130 evaluation board, which you can easily turn into a DSO with few passive components. Note that this project requires a code size of only 16 KB, so you can use the evaluation version of the Keil CARM compiler.

Implementing the oscilloscope was not my main task. I usually try new microcontrollers in video applications, so I figured this would be a good way to demonstrate the capabilities of the NXP (founded by Philips) LPC2138 microcontroller for generating a high-resolution (512 × 240 pixels) video picture.