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New user with #superpolaris


JoeC
 

Hello all.  I have two super polaris mounts that I'm looking to make more useful.  I have several questions though because this project is so versatile, but that means a LOT of options.
I am torn between ordering one of the boards and using a teensy and building on proto-boards with a mega256.  Which of the EasyEDA boards is the most "proven"?
Is the mega even powerful enough?  I have doubts since I moved to 32-bit on my 3d printers last year and they work smoother and I believe that matters with scope tracking.
I also have several nema 17 motor spares for my 3d printers, but they are all fairly large (I have amperage concern) and all 0.9 deg motors, is that a problem?  Do these require more processing due to higher steps/revolution or do the driver boards take care of this?
I'm very excited to find this project and see that there is an active group of people to talk with.
I have a lot of soldering experience and have built many board projects, I'm also a software developer by trade. So, hit me with info.


Lloyd Simons
 

Joe,

Did you check out the showcase page and the wiki? Several SP/CG-5 mounts have been converted to OnStep. The mega has been used successfully, but it does suffer in the performance category. I think many users are using ESP32 based systems for performance/cost. I converted a SP with 0.9° NEMA 17 motors using the Wemos R32/CNC V3 system and it works great. You just need to make sure the drivers you get will handle the required current for the motors. The build you decide to make is up to you and your needs.  

https://onstep.groups.io/g/main/wiki/4414


Khalid Baheyeldin
 

On Sun, Nov 15, 2020 at 06:50 PM, JoeC wrote:
I am torn between ordering one of the boards and using a teensy and building on proto-boards with a mega256.  Which of the EasyEDA boards is the most "proven"?
The MiniPCB, MaxPCB, MaxESP, and Blue Pill are well proven.

Is the mega even powerful enough? 
Not powerful, but can be adequate as long as your slewing speed is low.
It also suffers from an inaccurate oscillator. So you either autoguide and not worry about it,
add a 1Hz source (e.g. DS3231), or get a board that has a proper crystal (MKS Gen-L,
R32+CNC V3, S6 or any EasyEDA board).

I have doubts since I moved to 32-bit on my 3d printers last year and they work smoother and I believe that matters with scope tracking.

Good.

So you know that there is a difference, first hand ...

Because you are starting new, my recommendation is that there is no point it going for the lowest MCU anymore.

I also have several nema 17 motor spares for my 3d printers, but they are all fairly large (I have amperage concern) and all 0.9 deg motors, is that a problem?  Do these require more processing due to higher steps/revolution or do the driver boards take care of this?
Motors that are 400 step (0.9 degree per step) are the recommended motors, since they provide more overall reduction than 200 step motors.

If you have some of those, then use them.
If not, they are relatively low cost to obtain.

I have a lot of soldering experience and have built many board projects, I'm also a software developer by trade. So, hit me with info.
Depends on your needs?

Examples:

Do you plan to use a motorized focuser? If not, then any board would do.
Do you need more than one focuser? Then exclude the MiniPCB and Blue Pill.
Do you need the works: FYSETC S6.

What else do you need, so we can narrow it down.


JoeC
 

Thanks for the responses.  I appreciate the information.
At the moment I'm just looking to use goto and tracking.  Once that is done probably guiding.  I don't have a need for remote operation due to having a terrible yard for observing, so I have to go away from my house and probably shouldn't leave my equipment unattended.  And, in south Texas, it doesn't get too terribly cold at night.

After doing more research I've ordered pulleys and belts to begin the motor fitment with some of the 3d printed mounts I have found. Then I'll need to build a board.
Since the Blue Pill MCU is so difficult to find, I'll probably go with the MaxESP kit. It's fantastic and much appreciated that George is providing this service, sourcing parts can be a real pain.
I've never done anything beyond the old "clock" drive that the SP came with, so I'm sure I will struggle with learning all the capabilities of OnStep.
Thanks again!


George Cushing
 

I think by far the STM32 BluePill has been the most popular. How many have been built to completion? At the moment both the MiniPCB and the MaxESP3 are selling well. Bit of a contrast in the price of the processors. The Mini2's Teensy costs $23 when purchased in lots of 10. The ESP32 is about $6 in lots for $10. The difference is I can get the USA assembled Teensys in a few days. While the ESP32s take a month.

I think if you are new to all this the MiniPCB2 is the best option especially for a 
EQ-5 type mount like the SP. It provides the fastest processor (600MHz), is easier to assemble and program than the BluePill and more complex MaxPCB. While not feature rich as these controllers, the MiniPCB2 is compact for what it does provide.

With its aluminum enclosure it doesn't require much real estate, about the size of a pack of cigarettes (shown with a BluePill for comparison).

P1016802.JPG
P1016803.JPG

Virus-free. www.avg.com


tnut55
 

I would agree with that assessment.  However, I have built early MiniPCB, MaxPCB and Bluepill controllers.  I would say the MaxPCB was the most trouble free, followed by the MiniPCB (mainly due to the wonky issues getting the ESP01 to program).  The Bluepill was perhaps the the most confusing to get programmed just right and I suspect that the many requests for help reflect this.

On Tuesday, November 17, 2020, 10:16:09 AM CST, George Cushing <stm32bluepill@...> wrote:


I think by far the STM32 BluePill has been the most popular. How many have been built to completion? At the moment both the MiniPCB and the MaxESP3 are selling well. Bit of a contrast in the price of the processors. The Mini2's Teensy costs $23 when purchased in lots of 10. The ESP32 is about $6 in lots for $10. The difference is I can get the USA assembled Teensys in a few days. While the ESP32s take a month.

I think if you are new to all this the MiniPCB2 is the best option especially for a 
EQ-5 type mount like the SP. It provides the fastest processor (600MHz), is easier to assemble and program than the BluePill and more complex MaxPCB. While not feature rich as these controllers, the MiniPCB2 is compact for what it does provide.

With its aluminum enclosure it doesn't require much real estate, about the size of a pack of cigarettes (shown with a BluePill for comparison).

P1016802.JPG
P1016803.JPG

Virus-free. www.avg.com


Khalid Baheyeldin
 

On Tue, Nov 17, 2020 at 11:58 AM, tnut55 wrote:
The Bluepill was perhaps the the most confusing to get programmed just right and I suspect that the many requests for help reflect this.
You are partially right: the fact that the Blue Pill does not have an EEPROM on board makes it prone to soldering errors, bad DS3231, and so on. In addition to that, the manufacturing errors in some modules (wrong resistor R2), and the recent supply issues for 128K flash compound the problem.

But I would guess that the support requests that we get for the Blue Pill reflects that it is the most wide spread.
The last count we did several months ago was about 370 units that were sold as kits.
We don't know how many additional units were ordered directly by people.
I would guess that the MaxPCB and MiniPCB have much less than that, although that is changing because kits are available now.


JoeC
 

Thanks for the updated info, it has made me rethink my preferences.
I sent a message about ordering kits, but will probably switch the order to the MiniPCB2 based kit.  I have worked with the teensy platform in the past and liked them.
I flashed into an old RAMPS 1.4 setup I had just to get acquainted with the process and software.  I'm curious since I switched all my RAMPS based 3d printers over to the bigtreetech SKR boards, which are basically a 32-bit ARM based smoothy board, this might even be a good platform with the 5 motor controllers and mosfets.  In pre-covid times, the boards where about $25, plus they have add-on wifi and LED control modules.

Until I get my pulleys and belts, I'm stuck looking at motors spinning on my desk.
Thanks to everyone


tnut55
 

All 3 versions of my controllers work well and are quite stable.  

My bluepills were bought some time ago.  Aside from a couple of soldering joints, I never had any issues with them.

The only problem I have now is trying to remember which controller goes with which mount!


On Tue, Nov 17, 2020 at 11:13 AM, Khalid Baheyeldin
<kbahey@...> wrote:
On Tue, Nov 17, 2020 at 11:58 AM, tnut55 wrote:
The Bluepill was perhaps the the most confusing to get programmed just right and I suspect that the many requests for help reflect this.
You are partially right: the fact that the Blue Pill does not have an EEPROM on board makes it prone to soldering errors, bad DS3231, and so on. In addition to that, the manufacturing errors in some modules (wrong resistor R2), and the recent supply issues for 128K flash compound the problem.

But I would guess that the support requests that we get for the Blue Pill reflects that it is the most wide spread.
The last count we did several months ago was about 370 units that were sold as kits.
We don't know how many additional units were ordered directly by people.
I would guess that the MaxPCB and MiniPCB have much less than that, although that is changing because kits are available now.


Khalid Baheyeldin
 

On Tue, Nov 17, 2020 at 12:40 PM, JoeC wrote:
I'm curious since I switched all my RAMPS based 3d printers over to the bigtreetech SKR boards, which are basically a 32-bit ARM based smoothy board, this might even be a good platform with the 5 motor controllers and mosfets. 
Some SKR boards have an NXP LPCxxxx ARM microcontroller.
These have no support in OnStep.
Others have STM32F103C8, which is what the Blue Pill had (now superseded by the STM32F303CC)

We already have a faster controller with more devices supported in OnStep, the FYSETC S6 (MOSFETs,
thermometers, the works).


JoeC
 

Well, for some reason after all the hours of reading this group I just skipped reading about the FYSTEC board.  That's a really nice looking board.
For now I need to get over my first hurdle. Getting the motors mounted with good belt tension.  There are more options out there than I though there would be for motor mounting. So, this shouldn't be too bad.


Khalid Baheyeldin
 

On Tue, Nov 17, 2020 at 07:45 PM, JoeC wrote:
Well, for some reason after all the hours of reading this group I just skipped reading about the FYSTEC board.  That's a really nice looking board.
One possible reason is that the comparison question does not include the S6 (nor the F303CC, W32, ...)

https://onstep.groups.io/g/main/wiki/7118

That question on that page warrants its own Wiki page actually, and should include more than just columns of datapoints.
For example, heaters, fans, ...

Anyone wants to take that task?


John Petterson
 

On Tue, Nov 17, 2020 at 04:58 PM, Khalid Baheyeldin wrote:
That question on that page warrants its own Wiki page actually, and should include more than just columns of datapoints.
For example, heaters, fans, ...

Anyone wants to take that task?

Khalid,
I have a fairly limited exposure to all to various options having built only the MKS Gen L andFYSETC S6 versions, but I am willing to outline some ideas to provide a page for that decision making.  Give me a couple of days to get some ideas and I will start another thread about it.

Please see the attachment for a different suggested page - I have been frustrated by my inability to find the needed links for creating the environment to build this software.  The needed information is all there, but it is often buried two or three clicks and much scrolling down in other web pages.  I consider this to be a work in progress, but I think that it would be a nice addition to the web site as well.  Comments?

John


Howard Dutton
 

This Wiki page contains similar and in some ways more detailed information:
Uploading the Firmware

It would be useful to add links to the libraries associated with Config.h options here:
Configuration (Config.h)

The problem with having more than one reference is you end up with more work keeping it all up to date.  Note the absence of STM32Duino instructions is due to the Wiki being directed at release-3.16 which doesn't support that.  When release-4.x happens we'll set about updating the Wiki with that and other information.


George Cushing
 

For low cost and pure simplicity it's hard to beat the Wemos R32 with CNC V3. If you are content with control by USB and no bells and whistles be on goto and accurate tracking you can be up and going for under $20. But start adding features and you are beating a new path. 

Yes, the ESP32 and Teensy based controllers are the easiest to program. Especially the Teensy. I will often flash half a dozen at a blow. Once OnStep is compiled in the IDE all you have to do is attach the Teensy to the USB cable and select upload from the Teensyduino popup without returning to the IDE's Upload function. Six can be flashed in a couple minutes. Purchased by the dozen a Teensy 4.0 runs about $22 a unit delivered. That buys you more than 50 ESP32 development boards. While the ESP32 unit is more costly than the BluePill, if you take the cost of the DS3231 RTC and the USB RS-232 adapter needed for the BluePill the cost difference is minimal. Until you get to the STM32F411CEU6 there is no performance advantage over the ESP32. And there would have to be PCB modifications to use the F411, as well as, firmware tweeks.

So it seems to me, if you need 600MHz and a small foot print without all the features of the MaxESP3, then the MiniPCB2 makes sense. Otherwise, unless $2 BluePills return to the market, the MaxPCB @ $40 is the way to go.


Howard Dutton
 

On Mon, Nov 23, 2020 at 11:34 AM, George Cushing wrote:
For low cost and pure simplicity it's hard to beat the Wemos R32 with CNC V3. If you are content with control by USB and no bells and whistles be on goto and accurate tracking you can be up and going for under $20. But start adding features and you are beating a new path. 
And lets not forget Bluetooth is built-in too, one can really skip the WiFi entirely without giving up your "hand controller" (Android App, Sky Safari.)