Need help w/ setting up a newly acquired Mirac PC

[yantra3d]

I recently acquired a 1994 Mirac PC through an online transaction with the original intent of scrapping the motion control hardware and refitting it w/ some geckodrives and updating to mach3 control software & XP, etc...

However, much to my surprise the machine is in near perfect condition and I am still a little stunned at how lucky I am to happen across this little beauty and so there's no way I can even consider cannibalizing this thing - given the condition it is in. It really deserves a proper turn.

Anyway, I know very little about these machines but have spent the past day researching on this bb and have learned a great deal already. The machine did not come with the PC, software, manuals or rs232 cable, etc... I have just the machine, control box and main interface cable between the two.

I have already downloaded the software based on the information I've found here and am going to search for an old 486/DOS laptop I have buried somewhere deep in my garage and try to install the Mirac software on it. However, I will most likely try loading up DosBox or VmWare on my newer PC that's running XP and try to install the software under DOS emulation.

So, I have a few questions to start with:

1) Will this particular machine require a dongle in order to run it w/ the proprietary Denford/Mirac software?

2) Will a common "null modem" 25-to-9 pin style cable work for interfacing my pc w/ the Mirac's control box or is the cable wiring configuration unique to this application?

3) Is upgrading to USB a possibility with this particular version of the mirac pc?

4) Is the DOS version of the mirac software the most recent version that I will be able to use with this particular machine?

I would greatly appreciate any information or advice you fellows can offer on this machine.

Thanks!

[Denford Admin]

Looks like a great find !

1) Will this particular machine require a dongle in order to run it w/ the proprietary Denford/Mirac software?

The DOS software is now free but not supported by Denford - the flash codes remove the need for a dongle, and can be found here (flashes.txt):
https://www.denford.ltd.uk/index.php?opt ... &Itemid=51

2) Will a common "null modem" 25-to-9 pin style cable work for interfacing my pc w/ the Mirac's control box or is the cable wiring configuration unique to this application?

If the machine was destined for the USA, then a pin-pin cable is usual. Otherwise the PC-Machine cable would be a crossover one (from memory: 2-3, 3-2, 4-5, 5-4, 7-7)

3) Is upgrading to USB a possibility with this particular version of the mirac pc?

Not really - the only USB upgrades are available for Euro Rack Baldor controls. However, its not impossible to fit a current control card, but would required lots of effort and cost.

4) Is the DOS version of the mirac software the most recent version that I will be able to use with this particular machine?

I'm not sure if there is a different version of software for this type of control card - Sorry for being vague, but I don't know these old machines at all.

[Denford Admin]

Just found this previous post which may help with the s/w:

viewtopic.php?t=855&highlight=fanucld

[Mr Magoo]

A few tips...

- It's an LCB3 controller so will use MIRAC.EXE software.
- MIRAC.EXE software does not need a dongle (but will not run unless the machine is connected)
- The machine serial cable will be a cross-over cable, not pin-to pin
- Only DOS software is available for this controller
- Machine should have come with a Desk Top Tutor keypad. Keypad connects to the PCs COM1, Machine connects to PCs COM2. (it can be configured to use the QWERTY keyboard if you don't have the Tutor keypad)
- The Keypad serial cable is "straight through" type (unlike the machine cable)

Good Luck - Nice Find

[yantra3d]

Hey thanks a lot guys... I really appreciate that!

So, since I'm missing the stock keypad and will have to rely on a standard keyboard does this mean that I will need to plug the keyboard into the com1 port in order for the S/W to locate it, or can I configure the S/W to locate the keyboard if plugged into the default keyboard port? And what about a laptop which has the keyboard built into it - can I configure the S/W to work with it?

Thanks again for all your help!

[Mr Magoo]

You have a MIRAC.GO file with the software. It is a text file.

For use with a regular QWERTY keyboard and the machine connected to COM1 it should read...

IBM.RS2 1
$3F8 4 MACHINE
QDENFORD.KBD 1
18.2 0
VGA.CRT 0
MIRAC.APP

And if the machine is connected to COM2...

IBM.RS2 1
$2F8 3 MACHINE
QDENFORD.KBD 1
18.2 0
VGA.CRT 0
MIRAC.APP

By doing this you are fooling the software into thinking the Desk Top Tutor keypad is connected, and mapping keys on the QWERTY keypad to those on the tutor. Eg. QWERTY ALT-H instead of the Tutor HOME key, ALT-J is the JOG key etc.

The regular keyboard stays connected as normal, so should work with a laptop OK, but note that you can not use a USB-to-Serial adaptor with DOS software, and I suggest you read other posts here about recommendations not to run in a windows environment.

[yantra3d]

Thanks so much for the info, that is extremely helpful.

I'm hunting around to see if I can find a manual for the software, do you happen to know if one exists? I imagine it's a pretty basic prog and I can likely figure it out on the fly but it would sure be a great help to have some form of reference.

I went over the machine pretty closely last night and the only damaged part I found was the front panel "axis override switch". Aside from that there is a little rust on the spindle and motor pulleys that should be removed. But, everything else looks to be in good mechanical order.

I'm getting pretty excited to see this up and running.

[Denford Admin]

How about this manual ?

viewtopic.php?t=953

[yantra3d]

That's exactly what I was looking for... thanks again!

My next objective is to find a way to power the mirac pc. I only have 110/120v power here at my rental unit so my first thought is to use a voltage converter that will step-up to 220/240v. I found a converter that has a max capacity of 3kVA which I would think should be enough to power the mirac, however I'm a little hesitant to try this w/o having more feedback from other more experienced persons in the art of electronics.

Anyone have any thoughts or advice to offer on using a voltage converter like this one below for this application?

https://www.amazon.com/Power-Bright-Volt ... 000MY02LQ/

[Rabby]

Cant see a problem with the transformer but try not to draw the 3000w would ony draw 80% of this

[yantra3d]

Hey thanks for bringing that to my attention. 80% of 3000w = 2400w and the ID plate calls for an input of 240V @ 11A which equals 2640w. Do you think I would be safe with this? It's really close!

I wasn't able to locate my old laptop so it looks like I'll have to buy one. It might be easier to get my hands on a used pentium than a 486 is why I ask. I just might try running it under an emulated version of DOS before buying a dedicated pc.

Is there any advantage to having a 486/66 over a slightly newer 100mhz pentium for example?

[Mr Magoo]

I think the 3000W trannie will be OK. The machine will only pull full load current when the spindle is taking heavy cuts. Most of the time it is pulling much less than this. It realy depends on what you expect to use the machine for and the duty cycle you'll be using the machine to it's max cutting capacity.

Re your PC requirements, a pentium will be fine.
I remember running the machines fine on something like a P4 @ 1GHz and above - it's more important to make sure the PC has 2 'real' serial ports (not usb<->serial adapters or PCI serial cards). Then you can either put DOS on the machine, or if it already has windows on try the DOSBox emulator software.

[yantra3d]

So, I have hit a wall with the rs232 cable configuration. I have tried a combination of 9pin and 25pin cable connections between the pc and controller board with no success. I have tried altering the mirac.go file along the way but am consistently getting the following error upon launching the software:

Error <128> Software aborted

This error comes up almost immediately (directly under the initial line, "Denford Mirac CNC Programming v2.25 11 June 1997"). I am assuming that it is aborting after not locating the machine through the serial port.

I'm pretty certain that it's my cable configuration and possibly the .go file since the mirac manual mentions that the supplied 9>25pin Denford machine cable has some custom crossover links to it and I have been using either a straight-thru (pin-to-pin) cable or a common "null-modem" (full handshake) cable adapter.

My guess is that I will need to create a cable to emulate the denford one but I'm clueless as to how it should be configured. I have found several different bits of information on the forums here but nothing definite. In some posts I have read that I should only need a straight pin-to-pin cable but then the manual mentions the special cross-over wiring and not all the info here pertains specifically to the mirac pc so I'm really mixed up at this point.

FYI, I'm running DOS on an older laptop and it has one serial port however I am not using the denford keyboard.

BTW, can anyone tell me what the "18.2 x" line in the .go file represents? And what the heck is the macmirac.go file and do I need to be concerned with editing it as well as the regular mirac.go file?

I would greatly appreciate any help on this! Thanks!

[Martin]

The lead needed is the IBM - Machine

https://www.denford.ltd.uk/index.php?opt ... &Itemid=51

I think the 18.2 is to do with the clock speed.

There is only one .go file requiered. Guess you need the "Mirac.go" .

The standard Mirac.go file does not normally need altering.

The .opt file sets up the machine parameters

[yantra3d]

I can't thank you enough for your help... that should be exactly what I'm needing.

Does it matter that the wiring inside the control box doesn't match the cable diagram? I noticed that the color coding appears to be different than the diagram when compared to the wiring from inside the control box.

The wires all appear to be in the general area (pins 2,3,4,5,7) but the color coding is mismatched compared to the diagram. For instance, the diagram calls for the red wire to connect to pin 2 for transmit and the blue to pin 3 for receive, however (looking at the image below) the controller seems to be wired the opposite of this. And likewise the green and yellow wires appear to be swapped as well. Do you think this matters?

[Martin]

The drawing is for the external lead. PC to electrical box.

As long as you wire the connections as shown it will be correct.

[yantra3d]

Excellent... I will try this today and see how it goes.

Thank you for the help Martin!

[yantra3d]

It looks like I'll have to order the parts needed to build the machine link cable so I'll have to hold off a few days b4 being able to move ahead on this.

I have a question regarding the grounding of the shielded portion of the cable. According to the diag the shield connects to the "case" rather than pin 1 so where do you think would be the ideal place to connect these (drain wires?)? It looks like it's calling for both ends to be grounded to the "case".

Here's another small item that needs addressing... the axis override limit switch. By chance does anyone know of a replacement for this item, I can't seem to track one down.

Thanks guys!

[Denford Admin]

According to the diag the shield connects to the "case" rather than pin 1 so where do you think would be the ideal place to connect these (drain wires?)? It looks like it's calling for both ends to be grounded to the "case".

If you have metallic shells, then use their cable clamps to get a connection around the cable shield, to the metalwork of the PC and control box.
If you are just "lashing" something up, then try get the shields connected to the metalwork at both ends - maybe using the D-type screws to tighten onto.

As for the switch, I'm not sure if this is exactly the same, but will at least get you in the right place:
RS item 503008
https://uk.rs-online.com/web/2508770779.html

[yantra3d]

Thank you for helping me with that... I really appreciate it!

Well, I built a new machine cable based on the IBM compatible wiring diagram mentioned above (see image below) but am still getting the 128 error. Both ends of the cable are grounded and I wired everything up according to the diagram so I'm stumped.

I'm not sure why the diagram calls for the jumped pins (6-8-20) on the 25-pin end since none of the wires on the controller side appear to be connected to any of the pins called out in the diagram.


Does anyone know if there is a pause during the initial launch of the mirac software where it searches for the machine? The reason I ask is that it is launching directly into the <128> error line without any hesitation whatsoever and it makes me think that something else is going on besides the cable.

I have a feeling that it has something to do with the MIRAC.GO file. I revised it according to Mr. Magoo's earlier post since I didn't receive the tutor keyboard with the unit and am using the built-in keyboard from the laptop in place of it. Would the fact that I'm using a laptop make a difference by chance or would it have the same configuration as a desktop pc using an external keyboard?

Any ideas on where I could go from here to trouble shoot this? I would greatly appreciate any advice.