connecting PICStep 4.0 to pminmo's interface...

[b_cybe]

Have ordered some PCB for the PICStep and the 4 axis interface from pminmo's site. I am know a bit unsure how to connect them... well I think I know how to but some question still remains. Have made a little jpg on how I plan to connect them.


But what do I connect the Enable (Brake) to? And another thing I wonder about, can't I take the +5V regulated from the 7805 on the interface and use it on the PICStep? The last thing I wonder is how do I set up Estop on the interface, in the documentation it stands something about Estop terminal but where is that? And he also says something about that I have to add a jumper on pad J or L (???), but I don't make any sense of it... would be gratfull if someone explained these things!

[pminmo]

Usually my recommendation on the Enable/Brake is to jumper them together and run them to pin 14 of the DB25 on the interface, use pin14 as a drive enable then, lo is enabled. But per your diagram you need to add a wire to pin 1 of the picstep to pin1 of the associated axis connector.

Yes you should be able to use the 5V on the interface to run the PICstep logic. However, it does depend on the wiring. Don't route the 5V wires next to motor wiring.
Make sure you use a star ground wiring scheme.

Estop- two simple single pole normally open switches. The contacts of one wire to X6, when you press the switch is sets a latch. Wire a second switchs contacts to X7, that is a reset switch. So you hit one to set and latch, the reset when you want to unlatch.

At this point that doesn't do anything except illuminate or turn off LED7. Pads J and L are the outputs of the latch circuit. The are the opposite of each other signal wise. i.e. one will be 4+VDC when the other is near 0VDC, and in the other state they are opposite. Depending on what you want to do, you can wire either pad to pin16 of the db25 for example for the computer to see. You can wire one to a small 5V relay in your chassis to shut things down, or break the enable signal to all the motor drives...

It's quite flexable, which makes it more complicated.......

[b_cybe]

Thx for the help!
Ok... have updated my drawing. Have fitted in the estop and a relay to shut down the router. And tried to clean up the wiring some...

Star ground? I tought the gnd of the interface and the PICStep already were connected? (You have to pardon me if I have misunderstood, I am not to known with the star ground name....).
Do you mean it is a "advantage" to use an external 5V power supply for the PICStep?
Could the 5V from the interface be connected as shown on the new dawing?

Have also connected the Estop, and have wired a relay to pad L, this will activate the coil in the relay so that once the latch is set the router will stop (hopefully...). Since COM (on the relay...) are connected to NC only when the coil is off (wich it should be when pad L are 0V), dont know if I should connect any to NO on the relay though...

I have also connected the Enable/Break for all the PICStep input to pin 14....



edit: I see now that I forgot to add a connection between the 5V on the interface and the PICStep, is it just to add a wire from +5V on the interface to +5V on the PICStep, or do I need to do something "special", a bit confused on this since you say it depends on the wiring...

[b_cybe]

Found a 5V relay laying around together with some else electronic components, so I thought I should check it out that my relay coupling would work. So I an hurry I connected a 9V power supply to a 7805 and applied 5V to the coil in the relay. Then I had connection between COM an NO, but when I removed the 5V I had connection between COM and NC, so I think I have wired that part correct (I hope...). I will guess that by time I propably wire from one of the pads to the pin 14 on the DB25, but in the start I think it is most important that I can stop the router. I will add the connection to the PC afterwards as I get more experience on the program I am going to use....

I am still a bit unsure if the wiring from my last post is fully correct though...

[pminmo]

Sorry,
I must have missed the last post. There are so many on the zone here these days (Good thing) it is kind of easy to miss one. I'm better about catching them on my website board: http://www.pminmo.com/phpBB/
Actually the one side of the realy coil should go to 5V and pad L is mean to switch to ground. Make sure the coil current of the relay isn't greater than 200ma of the 2N3904.

[b_cybe]

Thats ok I guess you have many post to reply to, I will begin to post on your forum when I start assembling and test it (I am pretty sure it will be some questions at those stages too...). Anyway if I think correctly I can find the coil current by measuring the resistance in the coil and then use Ohms law to calculate the current of my relay.
R= 73,4 Ohm
V=RI
5V=73,4*I => I=68mA
Well it can be a bit higher because my multimeter doesn't get a 100% correct reading but it will not be 200mA...

Have made another version (pretty much the same exept from the coupling to the relay...).


I hope this one is correct. Now when the ESTOP is activated there will be 5V over the coil wich will swith the coil on, and this will connect COM to NO and shut down the router/dremel (propably dremel in the start...). When the ESTOP is reset there should be 0V over the coil and it is then off and COM is then connected to NC wich should reactivate the router/dremel...

[pminmo]

Looks correct.