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Author Topic: Mega 2560 build can connect but not slew or track.  (Read 3661 times)

telfish

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Mega 2560 build can connect but not slew or track.
« on: January 07, 2018, 14:17:56 »

I am bench testing a new build with a Mega2560 and two 8255 drivers. I have go to the stage where I can connect to Eqascom and get an RA and DEC returned. When first connecting I get a pulse from the steppers ad the "mount" is in the unparked position.

So far so good.

I can't however get it to park, slew, or track, no motion from the steppers which are not energized. I am using the Atlas/Eq6 config file.

The Board and drivers are known to be good, I believe my wiring from the schematic is OK.

Any ideas?
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TCWORLD

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Re: Mega 2560 build can connect but not slew or track.
« Reply #1 on: January 07, 2018, 14:38:47 »

I presume you are using the schematic from here: https://www.astroeq.co.uk/tutorials.php?link=/doku/doku.php?id=buildown

And have downloaded the firmware and config utility from the downloads page?
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Tom Carpenter (AstroEQ)

telfish

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Re: Mega 2560 build can connect but not slew or track.
« Reply #2 on: January 07, 2018, 16:29:38 »

Hi Tom.

Yes I used that schematic.

I downloaded the github repository, used the Utility to load the firmware, used the config utility to load the EQ6 file. Tested connectivity to Eqascom.

It connected to the mount, gave a home position and seems OK. However it will not park, just sits there parking, will not slew or track. As I said I get a pulse to the steppers when I connect to eqascom. Thereafter no response from the steppers.

Does the firmware depend on feedback from the driver board/steppers in order to update it's position etc?

Thanks for the help and great project. Have ordered a board/chips and cables to build the official version, it's good to learn the system until that arrives as I have all the Mega bits to hand.

Terry
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TCWORLD

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Re: Mega 2560 build can connect but not slew or track.
« Reply #3 on: January 07, 2018, 18:04:45 »

Hmm. Odd.

Could you try downloading the config utility (including firmware) from here: https://www.astroeq.co.uk/forum/index.php/topic,228.0.html
That's the latest version that has had quite a few updates made to it.

Also, do you see the position in EQMOD moving? When you set it to sidereal tracking, do the numbers for RA and DEC stay constant?
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Tom Carpenter (AstroEQ)

telfish

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Re: Mega 2560 build can connect but not slew or track.
« Reply #4 on: January 07, 2018, 19:11:35 »

Just tore the whole thing apart and rebuilt, Uploaded the beta firmware, tried on two computers. No change. Eqmod is talking to the MEGA the TX and RX lights are constantly blinking. The Ra updates at the same rate as the  time even if I ask it to track, DEC does not update at all.

Bit of a mystery!
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TCWORLD

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Re: Mega 2560 build can connect but not slew or track.
« Reply #5 on: January 07, 2018, 21:41:48 »

Sounds like it's stuck in programming mode, at which point it will partially talk to EQMOD as the config utility uses the same protocol, but all the motor functions are disabled.

You could try uploading an Arduino sketch that writes 0xFF to all addresses in the EEPROM (I believe there is an Arduino example sketch to do that called eeprom_clear). Then try uploading the firmware again.
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Tom Carpenter (AstroEQ)

telfish

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Re: Mega 2560 build can connect but not slew or track.
« Reply #6 on: January 07, 2018, 23:27:05 »

Thanks Tom. Will give it a whirl and let you know. Have you ever thought about re writing the software pin outs to allow use of the ramps 1.4 3d Printer boards?

It seems to me that a Ramps 1.4 3D printer board would be ideal. It has capacity for an X axis (RA) Y axis (Dec), slots for two focusers and a rotator. Plus there are several high amperage PWM outputs for dew heaters.

So 5 stepper drivers and the PWM. The ramps 1.4 board sells for around 7 dollars. Stacks right on top of a MEGA 2560 so little or no wiring except to the steppers.

https://www.amazon.com/gp/product/B06XZ46PDJ/ref=oh_aui_detailpage_o07_s00?ie=UTF8&psc=1

Not much more needed other than a couple of 8255 drivers for the mount. The others can be added later, so a total outlay is around $25 including the 2560.





Terry


« Last Edit: January 07, 2018, 23:28:42 by telfish »
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gehelem

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Re: Mega 2560 build can connect but not slew or track.
« Reply #7 on: January 08, 2018, 11:54:39 »

Hi
About cnc shields : i think it cannot work...
Enable pins are common to each driver, and step/dir are not on same ports...
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telfish

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Re: Mega 2560 build can connect but not slew or track.
« Reply #8 on: January 08, 2018, 13:23:30 »

Hi
About cnc shields : i think it cannot work...
Enable pins are common to each driver, and step/dir are not on same ports...

The onstep guys have it working well.  https://groups.io/g/onstep

https://groups.io/g/onstep/wiki/2D-RAMPS14


I have a working setup using a 2560. I however love and have used eqascom for 5 years and am really keen to get Astroeq working for me.
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gehelem

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Re: Mega 2560 build can connect but not slew or track.
« Reply #9 on: January 08, 2018, 22:11:25 »

 :)
Yes but they use different software...
Lets wait Thomas point of view to be sure
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telfish

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Re: Mega 2560 build can connect but not slew or track.
« Reply #10 on: January 09, 2018, 15:20:45 »

Just bought a new 2560 and programmed it successfully so my old one had issues somewhere. Thanks guys.
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