OpenDRO User's Guide

Release 1.0.0

Download the OpenDRO User's Guide 1.0.0


Table of Contents

1 Introduction

2 Features

3 Front Panel

  3.1 Axis Display

  3.1 Indicators

  3.2 Keypad

  3.3 LCD-200

4 Operation

  4.1 Absolute Zero

  4.2 Incremental Zero

  4.3 Absolute Preset

  4.4 Incremental Preset

  4.5 Number Review

  4.6 Number Offsets

  4.7 Fractional Numbers

5. Function Menu

  5.1 Speed Keys

  5.2 Position Menu

  5.3 Status Menu

  5.4 Define Menu

  5.5 Setup Menu

  5.5 System Menu

6 Scales

  6.1 Chinese Scales

  6.2 Quadrature Scales

7 Auxiliary Devices

  7.1 Tachometer

  7.2 Electronic Edge Finder

  7.3 SD Card Reader

8 Automation

  8.1 Lua Language

  8.2 Lua Shelll

  8.3 Lua Extensions

  8.4 Examples

1 Introduction

OpenDRO is the open source software that runs on the ShumaTech DRO-550 and DPU-550 digital read-out (DRO) systems.  It is designed to run on Atmel's SAM series of ARM7 processors and is developed in C with some ARM assembly in critical spots.  OpenDRO is architected to be generic and easily ported to new hardware platforms.

OpenDRO supports all known protocols of the ubiquitous Chinese scales that can be purchased at a number of retailers like Harbor Freight.  It also supports quadrature signals so you can use most glass scales and rotary encoders as well.  It features advanced adaptive moving average filtering to eliminate display jitter often associated with Chinese scales.

Positioning operations in OpenDRO are accomplished by "working to zero" where a number is entered into an axis and you move that axis to show zero in order to arrive at the destination.  OpenDRO supports both absolute and incremental zeros as well as workspaces to save working sets of zeros.  You can enter zeros with the keypad in incremental or absolute positions as well as using an electronic edge finder.

OpenDRO on the DRO/DPU-550 supports a three axis main display using 7-segment LED modules and also a two axis, external LCD display for the DRO-550 called the LCD-200.  You can see axis readings in either metric or imperial units and can also configure the number of decimal places displayed.  In addition to floating point, OpenDRO can also show tachometer readings, fractional readings, feed rates, and several other types of readings.

You can perform a variety of complex functions with OpenDRO.  It supports tool offsets, bolthole circles, diameters, centerlines, compound vectoring, and a number of other functions.  For multi-step functions, OpenDRO steps the user through each operation and you can move back and forth at will through each operation.

The most advanced part of OpenDRO is its automation interface.  OpenDRO uses the Lua scripting language to enable the user to enhance the functionality of OpenDRO as they see fit.  You can store and run Lua scripts on an SD memory card and run these scripts on demand from the keypad.  OpenDRO has an advanced shell with line editing, command completion, and history so you can easily experiment and test automation tasks from the USB or RS-232 interfaces.

OpenDRO is easily installed over the USB or RS-232 interfaces using either Microsoft Windows or Linux.  More information on the exact software upgrade procedures is found on the product pages at the ShumaTech web site.