Malte recently finished building a compact external display for three digital sliding calipers on his Wabeco F1200 milling machine.
As HackADay’s Mathieu Stephan notes, Malte managed to fit the disassembled calipers onto the machine and use them for positioning.
“Before embarking on this adventure, he noticed that there were similar projects present on the internet, but all of the calipers used had different data interfaces and protocols,” Stephan explained.
“The calipers that [Malte] bought have a mini USB connector, even though the interface itself isn’t USB. As he couldn’t find any information on that interface, he turned to his oscilloscope to decode the protocol.”
Ultimately, Malte decided to construct an AVR-based platform (ATmega168) tasked with reading the three calipers and displaying positional data on the dot matrix LCD show in the video above. According to Stephan, the AVR firmware is coded in a mixture of Basic and Assembler.
Interested in learning more about the three-axis AVR position indicator with digital calipers? You can check out the source code and schematics on the project’s official page here.
Atmel | Bits & Pieces 