Gina

Cut the number of buttons down to three and the driver connects. I'll take it back up to four next.

Decided to try eliminating a section of code that wouldn't stop compiling - 62 lines that i added that check that the actual logic levels on the pins. This is only a check that th output is right. But the error is not in that section of code. Next thing I can try is to reduce the number of buttons controlling the motors. This will mean editing a couple of lines, commenting out individual lines and commenting out a section.

Went through the code again and found some errors which I corrected but it still isn't working Oh well... I guess tomorrow is another day as they say

Done loads of code changes and additions with the result that the Astroberry Board driver doesn't work. I've been meticulously over the code and can't see what's wrong. I think I shall have to backtrack to where I had 4 buttons almost working - at least the rest of the driver was working, now it won't even connect. One little error in hundreds of lines of code can stop things working. Some errors are picked up by the compiler, others go through and just stop things working. The Astroberry Board cpp file is over 600 lines long! Low level coding can be very tricky!

I've modified the code and recompiled etc. but the result is not quite right. Strangely, the labels aren't coming out on the buttons properly. And there's a logic fault in that the green light doesn't come on. I think also that it could do with a fifth button of OFF to stop any possible focus shift once it had been set correctly. Think I'll add that before moving the code to the Focus driver.

Here are the allocation of GPIO pins for the motor control lines :- #define M0 RPI_BPLUS_GPIO_J8_15 // GPIO22 #define M1 RPI_BPLUS_GPIO_J8_13 // GPIO27 #define M2 RPI_BPLUS_GPIO_J8_37 // GPIO26 M0 controls Motor A, M1 Motor B and M2 Motor C. I could have called them MA, MB and MC but numerical designations are more customary.

Tutorial using Ubuntu Mate.

In sorting this out I have also seen how to determine the state of the lens cover by reading the Hall switch. I think I can probably dispense with the Arduino and do everything with the RPi. Reading the state of a GPIO pin as input was much simpler than I expected

With two state switches the switch is either ON or OFF but with the focus motor control it's one of four so setting one ON must turn all the others OFF. In fact there are three control lines that go to the motor enable pins. These want to be in one of four states :- LOW LOW LOW = all on HIGH HIGH LOW = Motor A on HIGH LOW HIGH = Motor B on LOW HIGH HIGH = Motor C on The GUI wants 4 buttons as represented by the line numbers above and logic then controls the three output pins. The last action is to read the three pins and set the lights on the buttons as appropriate. If a rogue state occurs with two lines on an error state exists and the result light should be turned red and an error message given. I have yet to find how to do this. An interim measure might be to show all buttons OFF. The code correspondence between the 3 pins and the 4 buttons is as follows :- 000 All 001 A 010 B 011 Error 100 C 101 Error 110 Error 111 Error I think the easiest way of implementing this would be with an array.

I think I shall firstly try reinstating the 4th switch on the Astroberry Board but with 4 states corresponding with All A B C with one-of-many function. Then if this works, transfer it to the focuser which is where it logically belongs.

System control removed successfully Now to try adding controls...

It's worked Now for the System control (the Restart didn't work anyway and I certainly don't want to shut down the ASC remotely as I'd have to power down and up again by going out to the observatory).

I shall take these edits one at a time to avoid confusion. I have edited the Raspberry Board header and cpp files (rpi_brd.h and rpi_brd.cpp) to comment out all references to the 4th control line which should remove this control from the driver (if I'm right). This is the first time I have tried to remove a control.

I have had a reply from the author of the Astroberry project, Radek Kaczorek, who has pointed me to an updated package and after editing as I require, now works I have only done minor edits to the files to remove the unwanted drivers and change the labels for the Astroberry Board driver. More serious edits will remove the unwanted 4th control and System Shutdown/Restart from the Astroberry Board driver and add motor selection control to the Astroberry Focuser, if I can manage it

Installing the Operating System and Astro software The Raspberry Pi uses a micro SD card as its main drive and this behaves the same as the hard drive on a computer except that this card can be removed and data read from it or written to it. In fact the way the operating system is installed on it requires it to be out of the RPi. This tutorial will describe how the operating system is written to the card, the system set up with computer name, user name and password and then further software installed to permit remote control via LAN and the astro software to capture images and control the hardware such as filter wheel and mount. You need an SD card reader attached to you computer. First job is to download the operating system on the main computer and write it to the micro SD card. Go to the Ubuntu MATE download page, choose the Raspberry Pi version (takes two clicks) and download it. Next is to unzip it and write the image to the micro SD card. I am now using Etcher for this as it works well with Linux (my main PC uses Linux Mint). This unpacks and writes the OS to the card in one go. Plug card into reader (with adapter if required), run Etcher and select the micro SD card - careful here not to select you HD or other device. Also select the downloaded file. Set Etcher going and a few minutes later the OS is written to the card. There is a script that has been written for installing the INDI drivers onto the card in the RPi that covers what we are trying to do. This is AstroPi3 and pretty much does it all. The instructions given repeat what I have written above. The lines of code can be copied and pasted from the web page into a Terminal window on the RPi. Applications > System Tools > MATE Terminal. Use Firefox on the RPi to go to the AstroPi3 page and copy/paste each command line to the Terminal window. Hint, 3 clicks selects the whole line for copying. The script installs INDI and a few other items of astro software but you don't have to accept it all if you don't want it. The script may be edited to comment out unwanted items but you need to be careful and know what you're doing though "it's not rocket science" It also turns on SSH so that further command lines can be added from the main PC through its Terminal window and SSH. At this time the human interfaces can be disconnected from the RPi. With this script you end up with a usable system that will capture images and control most of the astro equipment on the market. Controlling DIY equipment is another matter and one I'm looking into. The script takes an hour or more to run and has a few y/n responses needed. One other point :- I'm using an extra RPi for setting up the micro SD card that will then go into the RPi in my all sky camera (or other imaging rig). So the working RPi doesn't need to have all the human interface bits plugged in and that means the RPi card can fit into a smaller box - as long as the SD card is accessible. That's it for the standard devices, the next section will deal with adding 3rd party drivers.

INTRODUCTION Firstly, let me say that this tutorial, although similar to the previous one differs in certain very important ways as a result of the new operating system so please read all of it. The previous Raspbian operating system has proved problematic with recent versions and the creator of the astro software I'm using recommends Ubuntu Mate. I have copied some common parts and included information which is particularly relevant to those who have not read the previous edition. This is a tutorial explaining how to install an operating system and software into a micro SD card to use in a Raspberry Pi for astro imaging and control of the relevant hardware. The software to capture images, control camera cooling and other things such as the mount etc. is called INDI and provides a set of drivers to control all the hardware. The Raspberry Pi will run in what is called "headless" mode - meaning that no human interfaces are directly connected to the RPi - instead the RPi is connected to the local area network (LAN) using either Ethernet (preferred for speed and reliability) or WiFi. Everything is then controlled from indoors on a computer also connected to the LAN. This computer is called a "client" and the Raspberry Pi a "server". This tutorial will detail all the steps involved in installing the operating system and software - there are rather a lot of them, hence the need for a tutorial. I believe that anyone with some knowledge of computers should be capable of following these steps and setting up a working Linux based astro imaging system. The Raspberry Pi can be put on the pier (or tripod) or even directly on the telescope mounting and would replace a laptop for instance, reducing the use of long cables etc. Unfortunately, unlike with Raspbian, using Ubuntu Mate involves using a monitor, keyboard and mouse (or trackball) in order to set up the operating system and enable remote control before the RPi can be used headless in the observatory or on a tripod.

This is a tutorial explaining how to install the Ubuntu Mate operating system and astro software onto a micro SD card to use in a Raspberry Pi for astro imaging and control of the relevant hardware.

Camera works fine and using the different OS has cured the short exposure problem I can now get down to 32µs exposure so I shall be able to use the camera in daytime (when it stops raining!). I have been trying to install the INDI drivers to drive the GPIO pins but getting errors which I have reported on the INDI forum where the author hangs out.

I have succeeded in installing Ubuntu Mate on the RPi microSD card and set it up. Installed INDI and other stuff and have SSH access from my Linux Mint desktop. Now about to test the camera imaging then I can go on to installing the Astroberry drivers to use as a template to create what I want.

Been reading up on INDI and getting there - I think I may be able to work this out There is a switch option of "one of many" ie. like "radio buttons" so that would form the control for the lens control motors. viz. All A B C. So that's one point determined

Been inspecting the code for the PiFace INDI driver and found the stepper driver code is to suit the ULN2003 type stepper driver whereas the Astroberry Focuser is for the A4988 type driver. If I were to use the ULN2003 stepper driver for all the steppers I might run out of RPi GPIO pins. So it isn't just a matter of using the PiFace INDI drivers as that package won't do what I want. OTOH I reckon that by comparing the code for the two systems I should be able to add extra controls to the Astroberry Board INDI driver. Eventually I shall know what I'm doing

The Astroberry Project has be superseded by PiFace and the PiFace Board has 8 relays so the INDI driver for this could be used as is. Though best to change the labels.

Looking now at what control lines I shall need from the RPi if I go for full remote control - thinking it might be best to go straight for it. I suspect that if I go for just set it up and hope it doesn't change, I'll regret it. Basically :- Lens Cover - OPEN/CLOSE Dew Heater ON/OFF Camera Cooler - ON/OFF Select Motor A Select Motor B Select Motor C Hmmm... Astroberry Board has 4 controls. OK so 4, 5, & 6. only need 2 bits but overall there are still 5 control bits required. So this will need either two Astroberry Board drivers or one with the code modified. This will need looking into. In fact there are several of my imaging systems that could do with modified or new INDI drivers and I could do with conquering this. (If I can get my aging head round it!).

Makes little difference which stepper driver to use, both cost about a pound (even cheaper from China). Same with the 28BYJ-48 motors, only a pound each. The A4988 drivers are easier to connect and program but then the motors need the bipolar mod (just careful use of drill). This gives me an idea for the control. Astroberry Board driver for the functions outlined above and the Astroberry Focuser for actual focussing. The diagram below shows the basic connections for the A4988 driver module. The Astroberry Focuser driver uses SLEEP, STEP and DIR. These could be connect to all three driver modules and the ENABLE used to determine which motor(s) to drive. I'll sort out the logic for driver selection shortly.

Control could be :- 0 = A 1 = B 2 = C 3 = All OR 0 = All 1 = A 2 = B 3 = C