Whilst previous-school machinists typically desire the mechanical vernier scale on their trusty calipers, many users today obtain calipers with a electronic readout. These types often occur with supplemental functions like differential measurements, or a “hold” functionality for these conditions where by you have to maneuver the instrument someplace deep inside of a equipment. One more practical attribute is a facts url that allows you log your measurements on a pc directly rather of manually coming into all the values.
The VINCA-branded caliper that [Liba2k] purchased has these kinds of a information link attribute, which calls for a USB adapter that is sold individually. There is a micro-USB connector on the instrument alone, but as a substitute of employing a USB interface, this is applied to have a proprietary serial protocol — a style and design final decision that should to be categorized as a felony if you ask us. Fairly than buying the formal USB adapter, [Liba2k] decoded the protocol and constructed his personal interface named VINCA Reader that can join by way of both USB or Wi-Fi.
The serial format turned out to be a uncomplicated serial bus that clocks out 24 bits at a time. In order to adapt its 1.2 V signal amount to the 3.3 V utilized by an ESP32, [Liba2k] developed a very simple stage shifter circuit working with a handful of discrete components. The ESP can communicate with the computer via its Wi-Fi interface, for which [Liba2k] wrote a spreadsheet-like application alternatively, an everyday USB cable can be related to emulate a keyboard for use with any other software package.
With its included Wi-Fi characteristic, the VINCA Reader is actually a lot more full than the official USB adapter, and will almost certainly be much less expensive as effectively. The serial interface seems to be frequent to all caliper makers, even though several went for a additional reasonable connector than micro-USB. An automated readout method is specially handy if you have to make 1000’s of related measurements.