Adapter Board for Shahe and iGaging Capacitive DRO Scales

Monday, February 25, 2019
Capacitive Scale DRO Adapter

TouchDRO adapter for iGaging and Shahe scales is designed to work with several models of 3V capacitive linear DRO scales manufactured by Sanhe Measuring Instrument Co.,Ltd. and distributed under different brand names. It supports up to four linear scales, directional tachometer and a probe or tool height setter input. The circuit is designed and laid to provide reliable operation of capacitive DRO scales and significantly reduce the effect of shop noise and electrical interference on the scales, compared to a do-it-yourself adapter.

TouchDRO Supports new Chinese DRO Scales

Monday, February 4, 2019
TouchDRO "Black" Adapter Support All of The Shown Digital Readout Scales Now 

A few weeks ago, I finally found some time to experiment with the new Shahe Digital Linear Scales 5403-xxx and 5204-xxx. Electrically these scales are compatible with other 3V capacitive DRO scales such as iGaging DigiMag, EZ-View DRO and iGaging Absolute DRO. This means that adding support for the new scales is a matter of updating the firmware of the TouchDRO adapter for iGaging and Shahe DRO scales. After cursory check of scale protocol, I was expecting this to be a relatively easy addition to the existing firmware since they use the familiar BIN6 protocol. In practice, supporting Shahe "Remote DRO" scales ended up requiring a complete rewrite of large portion of the firmware. While at it, I decided to invest some more time into adding several other improvements that have been on my "to do" list for some time now. After several weeks of testing and debugging, the new firmware is ready to be released. In addition to the added protocol support, the updated firmware includes a few major performance and stability tweaks that will make capacitive DRO scales behave much more reliable in a shop environment.

Shahe 5403 and 5204 Digital Linear DRO Scales Overview

Sunday, January 6, 2019

For several years the so-called "remote DRO" capacitive scales, manufactured by Wenzhou Sanhe Measuring Instrument Co.,Ltd. have been the mainstay of budget do-it-yourself DRO setups. These scales first appeared in the USA around 2011 under iGaging brand as "DigiMag Remote DRO" or "DigiMag" but then started showing up all over the internet under various brand names, including AccuRemote, Shars and unbranded generic version. A few years ago iGaging has redesigned the display of the scales and rebranded them as EZ-View DRO. Around the same time Shanhe introduced two new models of the Remote DRO scales that look rather similar to the original model but have several key differences.

A few months ago I ordered a couple different lengths of each scale in order to test and reverse engineer the communication protocol, and finally was able to get to it over the holiday break. In short, these scales would work very well for a budget DRO build, but require different firmware to decode the position. As I'm working on adding the support to the firmware, let's take a closer look at the data format these scales use and other important characteristics.