russellhq

Thanks Louise. But the AT method requires clear sight of the east or west horizons, which I don't have from my observing location. I want to be able to polar align with any pair of points I choose.

Sounds interesting! I've been researching how to polar align using 2 plate solved images and then making the adjustment by re-centring an off-set star. Trying to get my head around the maths part but got the plate solving part sorted. http://webpages.charter.net/dware1/Projects/Polar_Alignment_Equation.pdf

Doesn't look like you have listed it. The driver has AAF2 in it's name, and I think the full name is "ASCOM Focuser Driver for AAF2".

Yeah, it's a powered hub. I've got the Atik and serial to USB cable from the mount also connected. I tried it without the other devices connected. I tried a bunch of different combination to see if I could narrow down the fault and recorded them in the table below. For each combination, only the focuser USB device was connected and it was uplugged before testing. I recorded the voltage across the Nano +5v and GND pins for info. I know very little about electronics so really don't know what the table is telling me, but all I need to know to make it work is to make sure the power is plugged into the hub and turned off before attaching the USB cable to the laptop!

It seems to be working again. I might try adding a separate power source, PP9 battery, and see if that helps with stability.

"USB device not recognised" Started getting this message a week ago, and solution was to unplug the focuser from the USB hub and plug it back in. Now that's not working and get this message every time I plug the hub (powered) into the laptop. I've tried plugging the focuser directly to the laptop and it's recognised and works, so seems the device is OK. Anyone else come across this error? Maybe I need a better quality hub?

Why not just get a nano when they are available for £3 from eBay? :-) you could also get the same stepper for an extra £2.

I'm not sure it's that important to remember the position. What is important is repeatability of the steps, which is what we have. Given that a focus run takes only 1-2mins, then using the absolute position of the focuser may not be necessary. The kludge seems to be working well for me and is giving repeatable behaviour. So for now, I'll be using it

I'm not sure about changing comm ports as the focuser always seems to be on comm 6 on my laptop. I have ran into scenarios where FM auto-starts the focuser but gives all sorts of errors in the FM log. And when I try to fix it by connecting through the dialogue, the comm port is blank and comm 6 is in the drop down for selection. This happens rarely and is difficult to reproduce. The way I thought about the saved position was like this. When installing a new focuser there's no way for the focuser to know what position it's in so it either has to be told from software or installed in a known position i.e. 0 and have the focuser wound all the way in. From then on the focuser can store the position and report back when connected. But looking at the way the AAF2 driver code is written, the client doesn't request the last saved position from the focuser, it requests it from the driver and assumes that the focuser reported it's last position when disconnected and this position is still saved in the driver. This won't be the case when the client is closed and the drivers variables and released. I think having the driver report a default position is much the same as entering a default position in the dialogue. I don't think it's absolutely necessary to remember exactly the last position because you would never use that as your focus point. You would always carry out a focus run and have a new focus position. Also, you might be able to use GetPosition() instead of savedPosition since the arduino is set up to default to position 1000. This might not work as well when disconnecting and reconnecting the focuser within the client. Maybe I'll give it a go and see how it performs.

It looks like the "savedPosition" isn't working as expected. I changed the code to the follow, restarted the laptop, loaded focusmax with autoconnect enabled and the position was set to 5000. i then moved the focuser to 5050, disconnected and reconnected from within focusmax and the position was saved as 5050. It must be that the focuser variables are lost when the program connected to the focuser is closed. // set initial position to saved position (from setup dialog or previous disconnect) if (savedPosition > 0) { aaf2.setInitialPosition(savedPosition); } else { aaf2.setInitialPosition(5000); }

I started with a fresh install with the latest driver and arduino sketch from Sourceforge and saved the following logs. The first set are from when I use the chooser and set initial starting position (tagged "Chooser"). The second are from when FocusMax loads the focuser on start-up (tagged "Startup"). Each time, before loading FocusMax I powered down the arduino to make sure no values were being saved on the arduino itself. AAF220141005095726_Chooser.txt Driver20141005095726_Chooser.txt AAF220141005095640_Startup.txt Driver20141005095639_Startup.txt

When I use the chooser and enter the position, focusmax uses the number I enter. If I don't use the chooser and let it connect automatically then focusmax was using 0. I think it may be to do with the way the driver starts up. If the chooser is not used. Maybe the arduino is not ready to give a value but that seems unlikely?

OK, I seem to have fudged a solution though not sure if it's going to have any undesired effects (haven't noticed any yet). I changed the following line to add "=5000" and that seems to work: internal static int savedPosition=5000; // tekkydave - to hold position passed from setup dialog or between disconnect / reconnectsI can disconnect and connect within Focusmax and the position is saved. But if I disconnect, close Focusmax and re-open Focusmax, the position resets to 5000.

Having a bit of bother with the driver and Focusmax. If I select to auto connect the focuser from the "Open -> Options" menu, when Focusmax starts, the focuser connects but defaults to position 0 and I end up with the same issues as before when the focuser started at 0. I was looking through the driver to see if there is a way to get it to default to a larger number, maybe 5000, but I couldn't figure it out (I'm sat outside imaging, so brains not working that fast!).

Good work Dave! You can use Focusmax to read the temperature, it's free. http://www.focusmax.org/downloads.html Obviously though, unless you have Maxim DL or CCDsoft, then you can't use it for actually focusing.

Couldn't find how to not use the device address, but found how to get the device quite simply. The following 2 lines of code assigns the address: oneWire.reset_search();oneWire.search(TempSensor);New sketch attached to post.AAF2r2.zip

I've ordered one now as well For the sake of a couple pounds, it looks a lot nicer!

No problem adding it to your project, you did all the hard work! Here's a crude sketch of the layout. Basically what you do is: Connect outer pins to ground Connect middle pin to a digital pin (my arduino code uses pin 6) Connect a pull up resistor of value 4k7ohm between your digital pin and 5v pin This arrangement is called "parasitic mode", which basically allows you to run 2 wires to the DS18B20 instead of 3. You can find out more about it here: http://playground.arduino.cc/Learning/OneWire You will also need to modify the Arduino code I posted to account for the serial number of your own DS18B20. I used the following sketch to find it: http://www.hacktronics.com/Tutorials/arduino-1-wire-address-finder.html Thinking about it, it's probably a better idea to incorporate the sketch into the focuser sketch!

And here's a picture of it on the scope: I need to trim down the screws at some point.

We have temperature sensing! Here's a screenshot from focusmax: And an extract from the log file: 23:04:20.042 AAF2 Constructed23:04:22.079 AAF2.setInitialPosition Sending: I1000#23:04:22.079 AAF2.CommandString ------------------ Start -----------------------23:04:22.079 AAF2.CommandString Command = I1000#23:04:22.079 AAF2.CommandString Clearing Buffers23:04:22.080 AAF2.CommandString Transmitting:I1000#23:04:22.330 AAF2.CommandString Getting Return Message23:04:23.160 AAF2.CommandString Return Message = I1000:OK#23:04:23.161 AAF2.CommandString ------------------ Finish ----------------------23:04:23.161 AAF2.setInitialPosition Received: I1000:OK#23:04:23.161 AAF2.getPosition Sending: P#23:04:23.161 AAF2.CommandString ------------------ Start -----------------------23:04:23.161 AAF2.CommandString Command = P#23:04:23.161 AAF2.CommandString Clearing Buffers23:04:23.162 AAF2.CommandString Transmitting:P#23:04:23.412 AAF2.CommandString Getting Return Message23:04:23.413 AAF2.CommandString Return Message = P1000:OK#23:04:23.414 AAF2.CommandString ------------------ Finish ----------------------23:04:23.414 AAF2.getPosition Received: P1000:OK#23:04:23.414 AAF2.getPosition Position = 100023:04:23.607 AAF2.getTemperature Sending: C#23:04:23.607 AAF2.CommandString ------------------ Start -----------------------23:04:23.607 AAF2.CommandString Command = C#23:04:23.607 AAF2.CommandString Clearing Buffers23:04:23.608 AAF2.CommandString Transmitting:C#23:04:23.858 AAF2.CommandString Getting Return Message23:04:24.393 AAF2.CommandString Return Message = C20.2:OK#23:04:24.393 AAF2.CommandString ------------------ Finish ----------------------23:04:24.393 AAF2.getTemperature Received: C20.2:OK#23:04:24.393 AAF2.getTemperature Temperature = 20.223:04:25.408 AAF2.getTemperature Sending: C#23:04:25.409 AAF2.CommandString ------------------ Start -----------------------23:04:25.409 AAF2.CommandString Command = C#23:04:25.409 AAF2.CommandString Clearing Buffers23:04:25.409 AAF2.CommandString Transmitting:C#23:04:25.660 AAF2.CommandString Getting Return Message23:04:26.199 AAF2.CommandString Return Message = C20.2:OK#23:04:26.199 AAF2.CommandString ------------------ Finish ----------------------23:04:26.199 AAF2.getTemperature Received: C20.2:OK#23:04:26.199 AAF2.getTemperature Temperature = 20.223:04:27.211 AAF2.getTemperature Sending: C#Also, I've attached the arduino sketch and driver cs files to the post in a zip file. AAF2r1.zip

Thanks Dave, got the code last night, took a bit of time to get my head around it but struggled to get it working. I added the following to the Arduino code to return a default temperature of 21.5 (and the counterpart in the driver code), but get an error in the client program (Focusmax). When I checked the log, it reports that the driver sent the command to the Arduino and the Arduino returned a string, but the sting was only "TT:OK#". Bit of a head scratcher case 'TT': // Get Current Temperature { Serial.print("TT21.5:OK#"); break; }

Dave is it possible to download the ASCOM driver project? I can't see it on the sourceforge site.

Hi Dave, I tried it out last night and it worked a charm! Had it running with FocusMax and it it did the job, just need to get up to speed with FM as I spent about 3 hours under clear skies messing about with it. To be fair, I was also trying out a new camera and an OAG for the first time, so maybe a bit much to try in one night Would be good to see temperature monitoring implemented, in fact I'm half tempted to do it myself if I find the time, although my coding is nowhere near as elegant as yours!

Positioned the scope to point at the zenith, attached the camera, OGA, guide cam, reducer and set it to retract. Everything worked! Thanks again Dave for this great bit of DIY!

New motor and control board arrived today. It's the same make and model but is much stronger, more importantly it turns the focuser! Next test is to see if it can turn it with the camera attached!