The BigTreeTech TMC5160 V1.2 work just great in the S6. Microstepping is set separately for each of tracking and slewing in the Config.h file as is the motor current (directly, not via Greg and a pot... the TMC5160 doesn't even have a pot). OnStep sets these parameters in the driver over the SPI interface.

On August 2, 2021 11:19:31 p.m. EDT, Samuel.anderson123@... wrote:

Thanks, I might go for the TMC5160 don't seem to be too expensive and i'd rather overate the driver. I haven't looked into how onstep works with the motors/drivers yet.
Can you just set the microsteps in a config file. i.e 128X or 64X? And can you set it to differently for tracking and slewing?
Also you mentioned 40-50% current of the maximum, how is the current set? In this example the Nema 17 max current is 1.68A @ 2.8V effective resistant of 1.66Ohms.
In order to get 50% current (840mA) i would need to set the output voltage to 1.39V somewhere. Is this done in onstep?

Thanks


 

 


On Sat, Jul 31, 2021 at 03:01 AM, <mdwsmith@...> wrote:

S109 are quite high current you may be able to get cheaper LV8729s, depending on the current draw of your motor - best practice is to use only 40-50% of the max motor current from wiki recommendations.

If you want a better compromise with goto's and accuracy TMC2130 (must be SPI version) or the higher current TMC5160 - these offer mode switching from high microsteps for accuracy tracking to low microsteps for goto.  Trade off is higher cost - maybe twice as expensive.

see https://onstep.groups.io/g/main/wiki/4464

--
Sent from my Android device with K-9 Mail. Please excuse my brevity.

Thanks, I might go for the TMC5160 don't seem to be too expensive and i'd rather overate the driver. I haven't looked into how onstep works with the motors/drivers yet.
Can you just set the microsteps in a config file. i.e 128X or 64X? And can you set it to differently for tracking and slewing?
Also you mentioned 40-50% current of the maximum, how is the current set? In this example the Nema 17 max current is 1.68A @ 2.8V effective resistant of 1.66Ohms.
In order to get 50% current (840mA) i would need to set the output voltage to 1.39V somewhere. Is this done in onstep?

Thanks


 

 


On Sat, Jul 31, 2021 at 03:01 AM, <mdwsmith@...> wrote:

S109 are quite high current you may be able to get cheaper LV8729s, depending on the current draw of your motor - best practice is to use only 40-50% of the max motor current from wiki recommendations.

If you want a better compromise with goto's and accuracy TMC2130 (must be SPI version) or the higher current TMC5160 - these offer mode switching from high microsteps for accuracy tracking to low microsteps for goto.  Trade off is higher cost - maybe twice as expensive.

see https://onstep.groups.io/g/main/wiki/4464

Hi Dave,

Thanks for the detailed response. I can get all of that from ALIexpress, i'll copy. Do you ever get a gps to work with the Fysetc 2.0?

On Sat, Jul 31, 2021 at 02:20 AM, Dave Schwartz wrote:

Considering your 'futures' list, I would recommend the FYSETC S6 2.0 as
the controller board. Its plenty fast, has 3 additional driver spots for
rotator/focusers, has onboard MOSFETs and screw terminals for directly
connecting dew heaters plus you can connect a GPS, ESP32 module for
simultaneous WiFI/Bluetooth operation, a BME280_SPI for ambient weather
sensing and dew heater temperature sensors for automatic heater power
control. I've done all of the above with an S6 except for the rotator.

On 2021-07-30 1:04 a.m., Samuel.anderson123@... wrote:

Hi Guys,

I've started my Dob conversion using Prosperguy thingiverse printed
gears. I have to do some fusion3D mods for it to fit my scope, never
used it, bit of a learning curve.
Waiting for some stuff that's on order etc. In the mean time I was
just trying to work out microcontroller, drivers, motors etc.
Could someone please check my proposed design below and let me know
your thoughts. Scope is a 10 inch GSO dobsonian.

1. The big gears (both ALt and AZ) will be 420 teeth and g2T belt
driven to a 20T smaller gear giving 21 reduction. (Happy to change the
smaller gear, don't know how to redesign the larger one)
2. I propose to use Nema 17 (200step) with integrated 100:1 gear box
to yield a total reduction of 2100. (happy to change if there's a
better option)
3. S109 drivers (Happy to change)
4. Teensy 4.0 (600Mhz) - fasters better? (Happy to change)
5. Some sort of wifi card. (Whatever Works)

I'm happy to design and make my own custom Circuit board and power supply.

What I want to use it for:

Lucky Imaging with high resolution tracking, happy for slow slew
speeds if it gets me more accuracy.
If I can also be greedy and have fast slew times of 5 degrees per
second that would be cool too, but not necessary.

How I want to use it:

Link Iphone via wifi with the tracking app to update time/location.
Open Sky safari for goto commands

What I'd like the possibility of upgrading:

Adding rotator for the camera
Adding Blutooth for that joytick control
Adding GPS for auto Location/time updating.
Adding humidity/temp sensor to calculate dewpoint and switching
heaters on/off (just the switching command is fine i'll work out the
power side)


Apologies in advance if any of the above is completely stupid and
won't work for obvious reasons.

Thanks.

Hello guys hope you all have a great day.

My OLED 1.3inch resolution seem out of range.
Anyone know how to fix this ?
Using SHC v1.03 version board with ESP32 and Bluepill board v1.8 with firmware 4.24.