Printer connectors

[samcrow]

why does the HS-1 have two printer connectors?

[romaxxcnc]

Hi Sam,

The left one is for the motion commands which all machines use and the second is for the closed loop connection. All the consoles now have both ports connectors installed. If no closed loop system is used, the ribbon cable for the second port connector is left folded up on the inside of the enclosure. It's there, if another port of communication should ever want to be used. For perhaps adding the closed loop encoder board.

Thanks, Ron

[yogert678]

Does this mean that a closed loop system can be added easily to an an existing machine?

[romaxxcnc]

Quote: "Does this mean that a closed loop system can be added easily to an an existing machine? "

Yes, the closed loop position monitoring system can be added at any time. The 2nd DB25 connector is installed in the console on all machines going forward. There is an area on the electronics panel to accomodate the interface. Would require adding an encoder to each stepper motor.

Judging by some questions we've gotten lately regarding the closed loop system we offer, it appears we haven't explained it very well. So I'll try again

Practically all PC based CNC systems sold by us and other vendors operate in an open loop configuration. i.e. The computer issues a command and the machine is supposed to carry it out. Generally that goes off without a hitch. Many machines run in this config, stepper or servo using a PC for command and many are very reliable, providing speeds and accelerations are kept minimal and all machining is kept to a "safe" level. A PC based CNC machine can skip, stepper or servo system, and the computer will just continue on oblivious to the lost position and subsequently ruining the workpiece (or worse).

Some servo systems available tout "closed loop", some clarification on that. The servo is closed loop back to the drive only. The computer still has no idea where the machine really is. The system we offer monitors position at the computer in the encoder DRO's on the settings page. The Romaxx is the only production machine in this class, that has this ability.

We wanted something better for our own personal machines and the machines we would eventually sell, hence the Romaxx. So we worked with an electronics logic design house and came up with the "Encoder interface" which essentially interfaces up to 4 encoders on a second parallel port to be read by the host software, Mach3.

The next step was how to handle the info being recieved back. First we used a "macropump" that pulsed 10 times per second and checked Encoder DRO's against commanded DRO's and would do a feedhold if there was a discrepancy. That worked well, but still not well enough. There were some issues internal to Mach3 with regard to homing and referencing and there was no easy fix or work-around strategy. We then contracted one of the software engineers with Artsoft to write a DLL plug-in expressly for our closed loop system. It works perfectly with Mach3. All features in Mach3 operate as a stock system. It is very non-invasive.

We offer the system, not because our systems need it more. Our machines are no different from a control standpoint than any other PC based controls on the market. Our electronics are top of the line "generic" in that respect. We own the software for it and we are the only one's that make it available for PC based Mach3 systems.

This system will presently only work with Parallel port communication. USB or Ethernet are not real time with the PC's OS, making realtime read of the encoders impossible at this time.

Hopefully this clears up some confusions in my prior confusing way of explanation

Thanks, Ron

[samcrow]

So this option requires TWO EPPs on the PC?

[romaxxcnc]

Hi Sam,

Yes, we include a second PCI parallel card and cable for the PC. Easy to install. Just make sure to use the driver from the included disc. The stock generic driver in XP for the Netmos 9805 will not work.

Then go into Control Panel/System/Hardware/Ports/Netmos 9805/Resources, the upper left 4 characters (i.e. C8A8) in the window are the port address. Enter that into Mach3, and tick the enable and tick "2-9 as inputs"

Thanks, Ron