Table of Contents
Advertisement
Advertisement
Table of Contents
Related Manuals for Onstep EQ5 GoTo
Summary of Contents for Onstep EQ5 GoTo
- Page 1 OnStep EQ5 GoTo BUILD INSTRUCTIONS By Oddvar S. Næss...
- Page 2 Corrections to the ST4 interface (pullup resistors) 21 May 2021 Information This instruction contains information not essential for building a OnStep GoTo System. For readers that want to jump right into the building instruction please go directly to the instructions page.
-
Page 3: Table Of Contents
Figure 8 - ST4 SIP unit soldered to the CNC V3 Shield Figure 9 - OnStep Controller with RJ45 Connectors Figure 10 - Motor brackets with RJ45 Connectors Mechanically assembly 3D Printed parts Additional items complimenting my setup, but not related to OnStep directly: Telescope and camera: Thank you! -
Page 4: Background
● It should function as a stand-alone system (no internet required) ● Ideally modular and portable A few evenings of googling made me bump into OnStep and a few months later I could finally confirm I had a fully working GoTo mount and celestial tracker that gave me very satisfactory results. -
Page 5: Building Instructions
Building instructions OnStep Controller Bill of materials Item: Qty.: Price ($) WEMOS D1 R32 ESP32 WiFi BT Development Board 7.00 LINK Arduino CNC V3 Shield 3.50 LINK LV8729 Drivers 18.00 LINK NEMA17 Stepper Motor 0.9deg 1.68A 40mm* 34.00 LINK GT2 12t 6.35mm bore 6mm belt pulley (DEC shaft) 4.00... -
Page 6: Software
Software Arduino IDE and configuration files 1. Follow the OnStep Wiki instructions carefully for setting up Arduino IDE correctly for flashing both the Wemos R32 and the ESP8266 (Link and Link). Pay special attention to Library versions! 2. Download OnStep V4.x Master File and extract to default Arduino sketch folder... -
Page 7: Electrical Assembly
Electrical assembly Connection diagram Figure 1 - Connection diagram NOTE: Wiki instructions for the electrical connections are excellent so make sure to read it before following the instructions on the next pages (Link). -
Page 8: Assembly Instructions
Assembly instructions 1. We’ll begin by cutting off the R1 (R5) 10㏀ resistor on the Arduino CNC V3 Shield to remove the pullup to 5Vdc as the Wemos R32 is based on 3.3Vdc: Figure 2 - R1 10k Resistor 2. The LV8729 drivers can be configured for 32 microsteps by inserting 2 jumpers on the CNC shield in slot M0 and M2 (also M1 and M3 on some versions). - Page 9 3. Now insert all the LV8729 drivers into their sockets. Make sure that the “En - Enable” pin is located in the upper left corner and that the Vref adjustment screw is pointing down or towards you when you have the shield oriented in such a way that all the text is in its normal readable orientation.
- Page 10 6. Now that we have the starting Amp for Vref we need to identify the actual Vref. However, the LV8729 seems to come in two flavours; some with 2x 100Ω resistors, and some with 2x R220Ω resistors. You find what version you have by checking the resistors on the underside of the drivers.
- Page 11 8. For those that would want to utilize the ST4 connection for a guide camera and/or hand controller the connections to the to CNC V3 shield should have a reference level (pullup to 3.3Vdc in this case). Otherwise these connections might act as antennas where stray voltages could change the logic level of the line and introduce noise, making the connection unstable and give spurious results.
- Page 12 (this is especially important for the DEC Axis) relative to where we mount the OnStep Controller on our rigs. I used RJ45 Breakout Boards for this. This way I could simply connect or disconnect the motors with standard network patching cables.
-
Page 13: Mechanically Assembly
Camera: Nikon D3300 and Nikon D750 Thank you! Thanks to the creator and all the contributors of OnStep I now have a low budget, wireless, highly accurate tracker and GoTo system. I’m now able to polar align the mount, do a one star alignment and then go inside and do everything else from my cosy warm sofa - no more hours of freezing in below zero celsius here in Norway for these night time photos.