AEQ-2018

AstroEQ with basic Remote Hand Controller

My latest version of AstroEQ DIY board (AEQ-2018 here). Designed in Fritzing and professionally printed by PCB online service (I used EasyEDA service, good quality and affordable prices). Email me if you are interested, I'll send you the Gerber files.

The board can communicate via HC-06 Bluetooth internal module or via 'classic' Mega2560's USB jack. External power source is anyway needed for Stepper motors electrical supply: 9-24V via AEQ-2018 board's Power jack, safe for the Step-down Buck Regulator. I tested these cheap Buck regulators and they works just fine. While powering the board up to 24V to over-voltage the 12V Steppers you'll obtain faster slew rates. The Buck converter output was set to 9V for the Mega's Vin pin and Fan.

In this controller, with respect to the previous ones, mainly I've added a resistors' voltage divider for the HC-06 RX pin and some LEDs and switches. More important, all components and board are boxed in a cheap plastic enclosure. I've also built a small and basic Hand Controller, based on the Tom's recent work about improved AstroEQ's capabilities. It can be used to control the AEQ-2018 as a stand-alone system.

Here below is a list of the main parts and components, relevant to my AEQ-2018 board.

... and, of course, Arduino Mega2560, Stepper Drivers and HC-06 module for Bluetooth.

The Mega2560's USB jack is accessible for software upgrading.

Board components

According to Tom's AstroEQ Arduino Mega DIY schematic:

  • C1-C3: ceramic caps 100nF
  • C2-C4: electrolytic caps 100uF
  • C5: ceramic cap 0.33uF (for voltage regulator)
  • C6: ceramic cap 0.1uF (for voltage regulator)
  • C7-C8-C9-C10: ceramic caps 10nF (optional for Hand Controller's buttons debouncing)
  • L7808 voltage regulator Step-up Buck Regulator
  • R13-R14-R15: LED's resistors
  • R21: 1K (for Hand Controller)
  • R22 and Q1: optional for future implementations
  • R23: 1K (for HC-06 voltage divider)
  • R24: 2K (for HC-06 voltage divider)

In the following image, the detail of the 8x2 Pins strips for external components connections.

I've placed a right angle male double pins strip because of the limited internal volume available in the plastic enclosure.

Due to the height limitation of the box I even had to remove the black plastic spacers normally present in the Pololu Stepper Drivers pins and reduce the pins length themself of about 2mm, in order to lower their upper surface with respect to the enclosure cover to avoid collisions (anyway, it's a pretty straightforward mod ... see image below)

https://photos.app.goo.gl/FZvYdLCENjSrWWEx9

I had to modify the mappings of the Arduino pins by slightly editing the PinMappings.h file in order to simplify the design of the board. Consequently, I recompiled the AstroEQ firmware from Tom's source (again, only the PinMappings.h has been modified to map the Arduino pins with respect to my board design).

I just tested my board using EQMOD/EQASCOM as well as in stand-alone mode with the Hand Controller and it works just fine.

Note about HC-06 mounting holes: there are two alternative places where you can solder the HC-06 mounting strip. The holes labeled as 'b' have to be used to mount the module as I did and shown in the present page, the holes labeled 'a' are 'flipped' and should be used if you want to mount the HC-06 upside-down. The labels Rxd, Txd, GND and Vcc on the board's white silk are relative to the 'a' option. For the 'b' option, the relevant V, G, T, R labels apply (they means Vcc, GND, Txd and Rxd respectively).

For the Hand Controller, I used a small OSD Menu Board plate (5 buttons cheap widely available module, normally used for OSD Menu control, link above). However, a small but easy modification on this type of board has to be made to make it usable as simple buttons plate (SMD resistors have to be removed, see instructions on my EAA Cam page here).

Diagram and description about the Tom's Hand Controller can be found here.

More images in the gallery above.

Installing firmware and configuring the AstroEQ

Once your AEQ controller was built you can upload the firmware in the Arduino Mega2560 and configure AstroEQ. You should have the AstroEQ Firmware Update Utility already installed on your computer (3.9.0 is the current version), available on Tom's Github repository in the Downloads section (AstroEQ-ConfigUtility).

    1. Go to the AstroEQ-ConfigUtility/hex folder and rename the original versions.txt file to something else, like versions_orig.txt, to keep it as backup
    2. Download the zip file (AstroEQArduinoMega2560_GG.zip, bottom of this page) and extract it in the same folder. Now you have two new files, the AstroEQArduinoMega2560_gg.hex firmware (modified to match my board's pin mappings) and the versions.txt that contain a dedicated line for the ConfigUtility
    3. Plug the USB cable between the Mega board and your PC (make sure the Bluetooth HC-06 module is not powered)
    4. Run the Config Utility AstroEQ.exe
    5. Select the COM port where your Mega2560 board is connected and in the 'Firmware' menu select 'Astroeq Arduino Mega 2560 GG'
    6. Click on Update Firmware

If all goes well you'll get a message like the following

Click on Next button

Complete the required fields in the Configuration window and click on both Update buttons. Save you configuration in a file using the dedicated button

Click on Done

Click on Next

The Utility will execute the EQMOD interface to test the controller

Click on Done to disconnect and close the EQMOD interface

You are now ready to test your AstroEQ controller via USB or Bluetooth ...

Hand Controller usage

Work in progress ...

October 2018

pierluigi.giorgi@gmail.com