Messages

1421

General Mach Discussion / Re: Mach & windows7

« on: October 24, 2010, 07:10:00 AM »

Thanks Gerry

1422

General Mach Discussion / Mach & windows7

« on: October 24, 2010, 06:28:30 AM »

Don't know if I've missed it somewhere but what's the state of play re: windows 7 and Mach?

Ian

1423

VB and the development of wizards / Re: modbus

« on: October 24, 2010, 06:22:12 AM »

Would that life was so simple. At the moment my THC is designed to work only with the hypertherm range as they're the only systems I've come accross that have a ready built in interface. I may look at a more generalized system at some point but here in Europe a system that requires the user to insert a custom interface into a plasma unit presents quite a challange from a H&S/legal/warranty perspective so I'm not sure there's any milage in it sadly - unless someone can tell me otherwise.

Ian

1424

VB and the development of wizards / Re: modbus

« on: October 23, 2010, 11:58:17 AM »

Hi Scott

I've not been able to find anywhere in the wiki where you can WRITE to a modbus slave from Mach OTHER than via autopolling. The wiki promises you can use direct access but gives you no clue as to how. I don't really want to use autopolling because all I want to do is send the reference voltage the THC should use for any particular cut setup. I just need to do that once per run when the cycle start is hit. The THC has enough to do without continually being polled unneccessarily so hence my desire to use direct access.

Terry

The THC is my own design - hardware and software and so I can make it use any protocol I like. I thought I'd try modbus because it seemed the obvious way to communicate with a bespoke device via serial from Mach - BUT I guess not. Like I said earlier, I'll just re-jig the serial hardware interface and use Mach's sendSerial. All other comms between the THC and Mach are done conventionally via Torch On/Up/Down etc. it's just that one serial tx I need to send the required voltage.

Thanks both

Ian

1425

VB and the development of wizards / Re: modbus

« on: October 22, 2010, 04:12:36 AM »

What did not work about the send serial, that is an 8bit transfer.??

The problem with sendserial is that it isn't session based. It opens the port, sends the data and closes the port again. The way I've designed the THC is that it treats a port open as the start of a session and resets the MCU. If sendserial is what I have to use then I'll re-jig this - just thought modbus might be the way but I'm going off it by the minute!

I agree it seems a read is trivial but not a write - strange. I may be wrong but I'm getting the feeling that Mach's modbus protocol is non-standard and has been fudged to work with particular hardware rather than with any general modbus slaves. I'll keep at it for a short while and see where I get.

1426

VB and the development of wizards / Re: modbus

« on: October 21, 2010, 11:04:55 AM »

IAN look in the Mach wiki under Mach subfunctions it gives the basic VB  commands and syntax to talk to a modbus device. It shold be what you need.

(;-) TP

I'm currently ploughing through this BUT there doesn't seem to be anything other than using autopolling. There are hints that direct access is possible but no explanation of how. I'll keep reading.

All I want to be able to do is send an 8 bit DRO value to my THC when I hit a screen button (required torch voltage). I've looked at sendserial but there are issues that make it less than ideal. I thought modbus would be the way but now I'm not so sure - it seems to be about the most complex method imaginable to send a few bits of data.

1427

VB and the development of wizards / modbus

« on: October 21, 2010, 05:02:58 AM »

Anyone know how to send a byte or a word or indeed anything from Mach VB to a modbus slave (direct access - not autopolling preferably)? I can happily read/write data from/to my slave's holding registers using the Mach modbus test interface - but how to do with VB?

The wiki teases us with this:

Direct access to Modbus registers

There are occasions when a VB Script writer needs direct access to Modbus device registers. This is provided by an interface which allows reading and writing of a block of one or more registers into Mach3 buffers (distinct from the autopoller buffers) and routines for accessing data in the buffers.

But sadly no mention that I can find of WHERE these elusive VB calls are documented.
Any seasoned modbus gurus out there?

Cheers

Ian

1428

General Mach Discussion / plasma torch volts control

« on: October 17, 2010, 02:09:48 PM »

under ports n pins/spindle setup down at the bottom right there's a checkbox for "torch volts control"

looks intriguing - anyone know how it's used?

Ian

1429

General Mach Discussion / Re: plasma anti dive

« on: October 14, 2010, 01:43:47 PM »

Terry - you've cracked it - here's the pertinent bit from Tom's manual: This is apparantly another "legacy" function.

"SLOW DOWN ANTI-DIVE. Anti-Dive Button. Turns ON/OFF the software Anti-dive. The trigger point where it locks downward movement is a percentage of the running velocity (XY combined) and is set in the Anti-dive DRO."

To be honest - the accel is good enough on my machine that it doesn't dive for this reason anyway, but the reason I wanted to know about this is I'm designing a new plasma screenset and wanted to know whether I should include this feature.

Really appreciate you taking the time to sort this for me - thanks

Ian

1430

General Mach Discussion / Re: plasma anti dive

« on: October 14, 2010, 03:42:56 AM »

Which function are you talking about?

what I'm referring to is the more simplistic anti-dive that comes out of the box with Mach - i.e. a software thing rather than hardware. The problem it's meant to prevent is that when you slow down round (say) a sharp corner, this causes the torch volts to rise. This fools the THC into thinking the torch to work distance has increased so the THC sends torch DOWN to Mach. Ouch - Crash.

So to get round this you can set an anti dive speed in Mach (OEM 82) which basically says if you go slower than this then ignore the UP/DOWN signals from the THC. It's enabled/disabled  with OEM 221 or with OEM 222,223.

in the mach2 mill manual on the downloads page section 6.2.13.1.