[CNCMAN172]

Shelby you can prove it to yourself, just take a resistor from say 1000 ohms up to 4.7K and connect it to the direction signal and other end to 5 volts

It will work

[Shelby5041]

Hi
Can someone look st page 25-28 of slo syn manual

Regarding opto isoltar wiring...i dont understand this section

Mine has an opyo isolator 5v input red wire and 5v output red wire and then both jumpered

I test both input and output snd get 5v

This is orig configuration but is this ok for my current configuration with mach3?

See attached pic

[CNCMAN172]

You unit has a built in power supply for the opto interface. If you use the internal power supply you jump out to in which is how your units are wired. You can leave it that way it will work fine

Russ

[Shelby5041]

Thank you

Before i add a cheap 5 axis mach3 bob...can someone confirm the logic high output voltage value that is output from the bob to dir pin.

Is it 5v?...if its also 3.5v then this will not work for me.

[dazp1976]

Shelby,
The PC parallel port has never output 5V signals, it was always spec'd as a TTL interface, so 3.7 to 3.8v was normal for a high signal, and low was usually about .5v. What is wrong is your parallel port card does not contain pull up resistors and it is using open collector transistors to drive the output signals. Most basic BOB cards like cnc4pc c10R cards do NOT require a 5V power supply or any other supply. They pull the required voltage right off the parallel port. There card is $23, but you can select pull up resistors or pull down resistors.

https://www.cnc4pc.com/c10-bi-direct...face-card.html

Russ

Wrong.
Read page 3 of manual
Quote: "A 5v of 500a minimum power supply is required to power this board".
I kid you not. All bobs need a 5v supply to run the isolators, buffers and pull ups/downs.

RTFM!

[dazp1976]

Thank you
Before i add a cheap 5 axis mach3 bob...can someone confirm the logic high output voltage value that is output from the bob to dir pin.
Is it 5v?...if its also 3.5v then this will not work for me.

Try something for me.
Put 0v to the dir pin and it should spin 1 way.
Put 5v to the dir pin and it will run the opposite way.
That's how true TTL pport IO works.
It either turns voltage on (high) or it turns it off (low).
Thats it.

Pport has always been below 5v which is why bobs need a 5v external supply to run their internal logics.
Many just have a USB connector to take the power from USB pc port for a simple fix.
The ones that have the extra 12v input are so that 1. you can control a spindle as well and 2. use proximity sensors at a more reliable voltage.

[dazp1976]

Thank you
Before i add a cheap 5 axis mach3 bob...can someone confirm the logic high output voltage value that is output from the bob to dir pin.
Is it 5v?...if its also 3.5v then this will not work for me.

If you're talking about the ones with a usb port next to pport and have the relay on it too. Then......
You'll either need to take 5v from your pc via usb (you should get a USB cable with board) or get a small 1A 5v supply for it (into pc5v marked pins) if you have no usb ports (old old pc).
It needs this to run the 2 large buffer chips on the board.

I got about 4.7v from mine through the USB route.


TIP:
If you get a long 4 pin pc molex extension cable you can plug this into the inside of pc and take the 12v from the yellow and black wires. Just remove a pci cover blank and stick the wire out the back.
Just check inside pc to see if there is a spare molex connection available.
Now you don't need an extra 12v supply.

The 12v powers the input isolators on the internal logic side, you can still use any voltage npn limit switches on your controls side.

[dazp1976]

Try something for me.
Put 0v to the dir pin and it should spin 1 way.
Put 5v to the dir pin and it should spin the other way.

TO CLARIFY.
When I said this earlier. Where I said 0v I meant LEAVE IT DISCONNECTED. Not put the 0v/GND to it!. I meant 0v as in nothing.
I should have been clearer.

[CNCMAN172]

As has been noted many BOB do require an external power supply depending on the features found on the boards. Some require no added supply, most of those are older very basic models. Here is an example of a good BOB with a manual, many Chinese units from ebay come with no manuals and no schematics. Look at page 6 in the attached manual and you will see they schematic of the interface that shows the pull up resistors.

Attachment 479066

Attachment 479068

Your current parallel port does not have pull up resistors, so the outputs are from open collector transistors. If you measure the voltage at the output pins like pins 2 and 3, when not being activated they will measure a TTL level high about 3.6 to 3.8 volts. However, if you attach a load to those outputs the voltage will fall drastically because there is no pull up holding the collector high and so there is no path for the current to flow. So under load the voltage will actually be less than 2 volts. The reason the pulses coming from Mach3 will allow you to spin a motor is they are pulling the outputs low and the open collector goes up just enough to allow it to work. However, when you try to use direction signal it works in one direction when it pulls the output low, but the high will not work because the current can not flow through the collector of the transistor when requested high.

Russ

[CNCMAN172]

One additional point your drivers have a built in 5V supply, which is probably large enough to power the few integrated circuits on the typical breakout BOB like the C10. This is the built in 5V supply for the Opto interface. You could use that our you could run a wire from a spare power cable from your PC power supply that is normally used to power disk drives or CD drives. Those cables have both 12V and 5V. The red wire is typically the 5V lead, and the orange wire is the 12V lead, but measure with a meter to be sure on your specific power supply.

Russ

[dazp1976]

As has been noted many BOB do require an external power supply depending on the features found on the boards. Some require no added supply, most of those are older very basic models. Here is an example of a good BOB with a manual, many Chinese units from ebay come with no manuals and no schematics. Look at page 6 in the attached manual and you will see they schematic of the interface that shows the pull up resistors.
Your current parallel port does not have pull up resistors, so the outputs are from open collector transistors. If you measure the voltage at the output pins like pins 2 and 3, when not being activated they will measure a TTL level high about 3.6 to 3.8 volts. However, if you attach a load to those outputs the voltage will fall drastically because there is no pull up holding the collector high and so there is no path for the current to flow. So under load the voltage will actually be less than 2 volts. The reason the pulses coming from Mach3 will allow you to spin a motor is they are pulling the outputs low and the open collector goes up just enough to allow it to work. However, when you try to use direction signal it works in one direction when it pulls the output low, but the high will not work because the current can not flow through the collector of the transistor when requested high.

Russ

And look at page2.
Quote: "A power supply 5V@ 500ma is required to operate".
The red arrow points outwards but it's an input for said supply.

You still need an external supply to run the logics and pull ups.


May as well buy the cheaper 5 axis ones and use the USB to get said external power.
They have exactly the same buffer chips so performance is exactly the same.

[dazp1976]

One additional point your drivers have a built in 5V supply, which is probably large enough to power the few integrated circuits on the typical breakout BOB like the C10. This is the built in 5V supply for the Opto interface. You could use that our you could run a wire from a spare power cable from your PC power supply that is normally used to power disk drives or CD drives. Those cables have both 12V and 5V. The red wire is typically the 5V lead, and the orange wire is the 12V lead, but measure with a meter to be sure on your specific power supply.

Russ

The orange is 3.3v.
The red is 5v.
The yellow is 12v.

Basic pc builder knowledge.
https://i.pinimg.com/originals/56/f4...c42797e5c8.gif

[CNCMAN172]

dazp1976,
I know the one I suggested requires a power supply, that is why I told him to either use the opto power suppy if it is big enough or the PC supply using an unused disk drive power cable. The USB idea is not a bad idea at all, however the Chinese cheap examples on ebay come with no manuals and you cannot determine if they are equipped with pull up resistors. The reason I suggested the one from CNC4PC is I have this model myself and know it works and it configurable with either pull up or pull-down resistors. I do think the BOB regardless of which one he selects is a good idea because it also protects the parallel port. This was especially important on older motherboards which had the PC port directly embedded on the motherboard. Parallel cards are getting harder and harder to find these days.

If he has some resistors and a DB25 connector he could build something really simple with soldered resistors to DB25 and run wires from this connector to the drivers, using the 5V supply for opto.

Attachment 479070

Personally, I would get a BOB, especially if he has not soldering equipment.

Russ

[Shelby5041]

Im trying to wire mach3 bob y axis only to test

But not sure how to wire to these drivers

[Shelby5041]

Hi..im trying to hook up mach3 bob y axis only for test

Im mot sure how to wire to these old stepper drivers

Im using 5v via usb port

Amd i connected step and dir pins from bob to drivers

What else i need to hook up.from the bob..gnd?...enable?

Thanks

[CNCMAN172]

Shelby,
With that style of BOB, you first need to plug in a USB cable which is how the board gets 5V power from your PC. Second to test the Y axis only you will need to run output #4 (step-Y) to PU input on the driver. Second you will connect output#5 (direction-Y) to CW/CCW pin on the driver. Third you need to connect Pin#25 or any other pin on the BOB that is ground and connect that to Logic common on the Driver.

Now when you tell Mach3 to move your Y axis everything should work.

Russ

[Shelby5041]

Hi

Thats exactly whst i did before i posted today and axis would not move in any direction...i do have 5v at pu and cw ccw pins though.. i used same mach 3 settings as before since the step dir pins were same 4 and 5...


UOTE=CNCMAN172;2506200]Shelby,
With that style of BOB, you first need to plug in a USB cable which is how the board gets 5V power from your PC. Second to test the Y axis only you will need to run output #4 (step-Y) to PU input on the driver. Second you will connect output#5 (direction-Y) to CW/CCW pin on the driver. Third you need to connect Pin#25 or any other pin on the BOB that is ground and connect that to Logic common on the Driver.

Now when you tell Mach3 to move your Y axis everything should work.

Russ[/QUOTE]

[Shelby5041]

Here is a lovely pic of the the engraver electronics before i hooked up mach3 bob

[CNCMAN172]

This is a very simple interface with a power supply for motor drivers. Do you have a logic probe to see if you are seeing pulses on the PU pin? Most people do not have a scope to check the signals. Do you know that Bob is good? This should move with no issues

Russ

[CNCMAN172]

You can make a simple probe with an LED and a resistor say 1K and test it on 5v dc supply to see if it lights up then once you know it works connect common on negative leg and connect other side ti signal you want to test

Russ