Re: [CAD_CAM_EDM_DRO] Re: The mechanical part of my router is done!

On Fri, 18 Jul 2003 14:54:03 -0500, you wrote:

>Thank you Harvey, and everyone. Thank you very much! I love this group...
>
>Now, another question...acronyms have always confused me. Could you
>clarify?
>
>>1) most interfaces want to see step and direction, I'd rewire for
>>that.
>>
>
>I know TurboCNC does...thankfully it's a very flexible program.

That's what I am using.

>
>>1) break the wire connection between the internal 5 volts and R1, R2,
>>and pin 7 of OCA. Break the connection to pin 8 of OCA, and to pin 7
>>of OCA.
>>
>
>OCA? Not sure what this is...optocoupler, perhaps?

OCA is the designation on the schematic of the optical coupler section
A, ditto with OCB.

>
>>Imagine a 5 volt supply (separate!) on OCB going to the left end of
>>
>
>Same question...
>
>>With no common ground connection, and a separate 5 volt supply, this
>>board will now work on step/direction for the motors.
>>
>
>I'm just missing that one little bit of info.

I'm trying to refer to the items by the schematic symbol, nol the
parts designation. It's reasonable to do either.

>
>>All these mods will take is a bit of patience and a 5 volt supply.
>>Rshack ought to have one, make certain that it is wired so that you do
>>not have any common point to the board supplies. we are talking total
>>isolation (as much as possible here).
>>
>
>There is a Radio Shack in town, but thankfully I don't have to shop
>there. :-) I have plenty of 5V, 10, 12, 14, 15, 18V supplies, and
>more, thanks to a large number of laptops in my computer room. :-)
> Believe it or not, our RS is "known" throughout the area, as the most
>useless of all their stores.

Heh.. well, if you have a regulated 5 volt supply, I'd use it. What
you are doing is to allow that supply to run the LEDs in the
interface, and not force the computer to supply (in this case, source)
current from its parallel port. As others have said, TTL circuitry
(parallel ports) are much better at sinking current, not sourcing it.

We have several RS stores, some useful, some useless. If I don't need
it *now*, I will order it by internet.

>
>>>HELP?!
>>>
>>>
>>
>>See if all this makes sense.
>>
>
>Almost all of it. Thank you.

See if this clarification helps, please. Otherwise, please ask again.

Harvey

>
> -- Chuck Knight