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Arduinos and Microcontrollers ref: Rotary Table Mew 249

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JA09/12/2016 19:33:28
874 forum posts
49 photos
Posted by SillyOldDuffer on 09/12/2016 17:54:08:
Posted by Roger Williams 2 on 09/12/2016 17:42:35:

My first time with the Arduino Uno too, and after getting something like " done uploading ",, I get bugger all on the LCD apart from the light !!. Oops. Any thoughts anyone please, bearing in mind I dont really know what Im doing.

This could be another easy one I hope. Top left on the LCD DIsplay is a Blue Box with a small brass screw on stop. This is the multi-turn potentiometer that controls contrast. Try turning it with a small screwdriver (could need to go either way). Be gentle and don't overdo it - I broke one once.

Dave

The photograph was up-side-down in the article (just to show that I have had a good read of what is a thought provoking article).

JA

Engine Builder09/12/2016 19:39:26
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222 forum posts

sillyoldduffer,

I manged to alter the sketch to verify the key voltages and got similar results to your one.

If it helps other builders my LCD shield is badged DF ROBOT (Drive the Future)

This is the results I got.

  • NO_KEY 1023
  • RIGHT_KEY 0
  • UP_KEY 98
  • DOWN_KEY 253
  • LEFT_KEY 408
  • SELECT_KEY 639
SillyOldDuffer09/12/2016 19:56:37
5310 forum posts
1086 photos
Posted by JA on 09/12/2016 19:33:28:
Posted by SillyOldDuffer on 09/12/2016 17:54:08:
Posted by Roger Williams 2 on 09/12/2016 17:42:35:

...

...

The photograph was up-side-down in the article...

JA

My punishment for specifically referring to 'top left' of the photo in the text! Glad you found the article thought provoking, rather than baffling (I hope).

Cheers,

Dave

SillyOldDuffer09/12/2016 20:07:18
5310 forum posts
1086 photos
Posted by Engine Builder on 09/12/2016 19:39:26:

sillyoldduffer,

I manged to alter the sketch to verify the key voltages and got similar results to your one.

If it helps other builders my LCD shield is badged DF ROBOT (Drive the Future)

This is the results I got.

  • NO_KEY 1023
  • RIGHT_KEY 0
  • UP_KEY 98
  • DOWN_KEY 253
  • LEFT_KEY 408
  • SELECT_KEY 639

Good work, you're officially a computer hacker now!

My LCD is a DF Robot as well - perhaps they all produce voltages like that.

I haven't got any further than getting the arduino and display to work. I wrongly thought I had a suitable motor, lack of which has taken the wind out of my sales...

Cheers,

Dave

Engine Builder09/12/2016 20:34:00
avatar
222 forum posts
Posted by SillyOldDuffer on 09/12/2016 20:07:18:
Posted by Engine Builder on 09/12/2016 19:39:26:

sillyoldduffer,

I manged to alter the sketch to verify the key voltages and got similar results to your one.

If it helps other builders my LCD shield is badged DF ROBOT (Drive the Future)

This is the results I got.

  • NO_KEY 1023
  • RIGHT_KEY 0
  • UP_KEY 98
  • DOWN_KEY 253
  • LEFT_KEY 408
  • SELECT_KEY 639

Good work, you're officially a computer hacker now!

My LCD is a DF Robot as well - perhaps they all produce voltages like that.

I haven't got any further than getting the arduino and display to work. I wrongly thought I had a suitable motor, lack of which has taken the wind out of my sales...

Cheers,

Dave

Thanks for the help.

I'm on the next step now, ordered the driver!

Roger Williams 209/12/2016 22:27:15
331 forum posts
1 photos

Silly Old Duffer, thanks for that about the potentiometer, I tried many turns both ways but still nothing. I might try uploading again to see what happens.

JA09/12/2016 23:16:33
874 forum posts
49 photos
Posted by SillyOldDuffer on 09/12/2016 19:56:37:
Posted by JA on 09/12/2016 19:33:28:
Posted by SillyOldDuffer on 09/12/2016 17:54:08:
Posted by Roger Williams 2 on 09/12/2016 17:42:35:

...

 

...

 

The photograph was up-side-down in the article...

JA

My punishment for specifically referring to 'top left' of the photo in the text! Glad you found the article thought provoking, rather than baffling (I hope).

Cheers,

Dave

Certainly not baffling although I would not have started with a hot air engine.

Sorry. I think I have cross linked two threads again (that is this one is about the rotary table and I am referring to the hot air engine data logger).

JA

Edited By JA on 09/12/2016 23:23:54

Carl Wilson 410/12/2016 08:49:37
avatar
670 forum posts
53 photos
Interesting stuff, just seen all this. I'd no idea that the different Lcd/key pad Shields outputted different voltages.

Regarding the too bright Lcd, exactly same thing happened to me. Just adjusted the contrast pot as Dave points out.
SillyOldDuffer11/12/2016 12:27:39
5310 forum posts
1086 photos
Posted by Roger Williams 2 on 09/12/2016 22:27:15:

Silly Old Duffer, thanks for that about the potentiometer, I tried many turns both ways but still nothing. I might try uploading again to see what happens.

Hi Roger,

Oh dear you might have a dud.

Uploading again is the right thing to do. Keep an eye on the console display at the bottom for error messages.

The other thing to check is that all the LCD plug pins are correctly located n the Arduino socket. I once managed to bend one behind...

Good luck,

Dave

Roger Williams 211/12/2016 14:04:34
331 forum posts
1 photos

S O Duffer, thanks for your help, I will have another look at it tomorrow. Cheers.

Engine Builder11/12/2016 14:05:41
avatar
222 forum posts

Just been looking for a suitable motor for this project. The one in the article is said to be 24 kg/cm torque but looking at the source metioned I cannot see one with that specification.

I am confused too about the voltage rating of these motors. I assume a 12v is needed as that is the supply voltage.

The one closest to the specified one has a rated voltage of 3v and the one used in the Liming article seems to be 8.6.

i am confused what to get!

Neil Wyatt11/12/2016 14:17:39
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Moderator
17314 forum posts
690 photos
77 articles
Posted by Engine Builder on 11/12/2016 14:05:41:

Just been looking for a suitable motor for this project. The one in the article is said to be 24 kg/cm torque but looking at the source metioned I cannot see one with that specification.

I am confused too about the voltage rating of these motors. I assume a 12v is needed as that is the supply voltage.

The one closest to the specified one has a rated voltage of 3v and the one used in the Liming article seems to be 8.6.

i am confused what to get!

Steppers often have a supply voltage higher than the supply used, if the driver uses pulse-width-modulation this allows a high-voltage peak to overcome the inductance of the winding is and get better motion. A bit like how PWM control is smoother for slow running on model railways than lowering the driving voltage.

Neil

Engine Builder11/12/2016 14:30:24
avatar
222 forum posts
Posted by Neil Wyatt on 11/12/2016 14:17:39:
Posted by Engine Builder on 11/12/2016 14:05:41:

Just been looking for a suitable motor for this project. The one in the article is said to be 24 kg/cm torque but looking at the source metioned I cannot see one with that specification.

I am confused too about the voltage rating of these motors. I assume a 12v is needed as that is the supply voltage.

The one closest to the specified one has a rated voltage of 3v and the one used in the Liming article seems to be 8.6.

i am confused what to get!

Steppers often have a supply voltage higher than the supply used, if the driver uses pulse-width-modulation this allows a high-voltage peak to overcome the inductance of the winding is and get better motion. A bit like how PWM control is smoother for slow running on model railways than lowering the driving voltage.

Neil

It seems the other way around here though. The motors specified have a voltage less than the supply voltage.

Carl Wilson 411/12/2016 15:08:31
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670 forum posts
53 photos
The rated voltage of the motor will produce the rated current in the windings if applied gradually. we are applying pulses at a fairly rapid rate, so the inductance of the windings tends to prevent the full current building up. So we apply 12 volts to ensure that full current can flow.

The torque of the motor used is near as damn it 2 Nm. 1 kg cm is about 0.09 Nm. So 23 kg cm is roughly 2 Nm.

Edited By Carl Wilson 4 on 11/12/2016 15:12:25

Neil Wyatt11/12/2016 15:10:49
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Moderator
17314 forum posts
690 photos
77 articles
Posted by Engine Builder on 11/12/2016 14:30:24:
Posted by Neil Wyatt on 11/12/2016 14:17:39:
Posted by Engine Builder on 11/12/2016 14:05:41:

Just been looking for a suitable motor for this project. The one in the article is said to be 24 kg/cm torque but looking at the source metioned I cannot see one with that specification.

I am confused too about the voltage rating of these motors. I assume a 12v is needed as that is the supply voltage.

The one closest to the specified one has a rated voltage of 3v and the one used in the Liming article seems to be 8.6.

i am confused what to get!

Steppers often have a supply voltage higher than the supply used, if the driver uses pulse-width-modulation this allows a high-voltage peak to overcome the inductance of the winding is and get better motion. A bit like how PWM control is smoother for slow running on model railways than lowering the driving voltage.

Neil

It seems the other way around here though. The motors specified have a voltage less than the supply voltage.

Oops got my description back to front!

Most stepper driver chips limit CURRENT making the actual voltage relatively unimportant, within limits.

Engine Builder11/12/2016 15:22:47
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222 forum posts
Posted by Carl Wilson 4 on 11/12/2016 15:08:31:
The rated voltage of the motor will produce the rated current in the windings if applied gradually. we are applying pulses at a fairly rapid rate, so the inductance of the windings tends to prevent the full current building up. So we apply 12 volts to ensure that full current can flow.

The torque of the motor used is near as damn it 2 Nm. 1 kg cm is about 0.09 Nm. So 23 kg cm is roughly 2 Nm.

Edited By Carl Wilson 4 on 11/12/2016 15:12:25

So was it model number SY57STH76-2004A?

Carl Wilson 411/12/2016 17:15:38
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670 forum posts
53 photos
Short answer = Yes, that will do admirably.

Carl.
Engine Builder12/12/2016 18:09:45
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222 forum posts

The stepper motor driver arrived today.

Looking at the connections shown in the magazine article and the original article the wiring diagram was taken from I notice misleading information.

The article shows the 12v power connected to Arduino terminals gnd and vdd. There is no vdd terminal on the Arduino it is in fact vin.

The 12v supply to the driver board is shown as gnd and VMot. Again there is no VMot terminal, well not on my board, It should be gnd and +24.

In the article too there is no mention of what the DIP switches should be set to for stop current, excitation mode and decay setting.

Just mentioning this in case anyone else is confused.

Bazyle12/12/2016 21:36:18
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4984 forum posts
198 photos

Catching up with this it looks like I was well off in assuming it had an interpreter. Good detective work chaps, sorry for misleading you.. If it can work on Linux I must see if I can run the IDE on a Pie then I can play with one at work.

Carl Wilson 413/12/2016 05:59:06
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670 forum posts
53 photos
Don't be confused.

Vdd = Vcc = Vin = V+...ad infinitum. All terms that put very basically come down to "connect external within specified limits power supply here".

Same goes for Vmot, 24v, 12v....connect the power here. Ground is pretty much the same too.

There are so many variants of these boards that it becomes necessary to use blanket terms and assume knowledge on the part of the reader. In addition, I could have written an article the full length of the magazine, easily, but that can't happen. Hence a certain level of knowledge has to be assumed. What I did write then gets edited, in which I have no say or input whatsoever.

Switch settings. I set max step current to 2.6 A, erring on the side of caution. So Sw1 Sw2 on. SW3 and S1 off.

S2 to off. Microstepping doesn't give us much when we are driving a 90:1 worm gearbox so S3
and S4 both off. You'll have to tell the software you aren't doing microstepping as explained in the article. No decay setting so S5 and 6 off.

Hope this helps.

Carl.

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