Upload/Download

mmw asks:

</i>Oh, come on ... how hard is it to get Upload and Download straight!?</i>

Let's see how hard it can be.

What term do different brands of PLC programming software use for the transfer of a program from the programming device to the PLC and for the transfer of a program from the PLC to the programming device?

Typical terms are download/upload, store/load.

In GE Fanuc, 'Store' means to transfer a program from the programmer to the PLC. 'Load' means to transfer a program from the PLC to the programmer.

Have you ever downloaded files/music from the internet? I think this would be more appropriately called "upload". Nobody calls it that.....

Even PLC manufacturer's sites that have online manuals, firmware, and software upgrades call it "download".

Kinda strange!

when you "get" music from the web, are you transferring it TO a host or FROM a host? I believe the term download refers to the latter, as is the case when we transfer PLC programs. I don't see any difference.

Just because different manufacturers use different terminology, does that make this difficult?

Just looking at it from my P.C.

so then you're agreeing with me ... right?

Actually this is all semantics...the term(s) can be used either way. As Steve pointed out GE uses Store and Load
AB $ Siemens both refer to download as going to the PLC
DirectSoft32 doesnt show upload or down...its Write or Read

We can look at http://www.webopedia.com definition

download
To copy data (usually an entire file) from a main source to a peripheral device. The term is often used to describe the process of copying a file from an online service or bulletin board service (BBS) to one's own computer. Downloading can also refer to copying a file from a network file server to a computer on the network.
In addition, the term is used to describe the process of loading a font into a laser printer. The font is first copied from a disk to the printer's local memory. A font that has been downloaded like this is called a soft font to distinguish it from the hard fonts that are permanently in the printer's memory.

The opposite of download is upload, which means to copy a file from your own computer to another computer

The reference implies that your computer is the Master or Main point of reference. As we know PLC's started before computers were a common consumer product so in keeping with thinking along the lines of industrial automated equipment then the PLC is the MASTER or main device when connected. In other words you should think of the PLC as your computer and your computer as the connection to files etc(like a website or server).

Acually I am glad this subject was brought up.

Leave it to a TN boy to get down to the nitty-gritty. Thanks for setting everyone straight.

now, let's go "git that jenkins critter" (just kidding Tom )

Yeah, too many programs use Upload/Download in unclear ways. Mostly backwards.

Wish PLC software writers woould just use 'Send to PLC' and "Get from PLC'. Or "Load PLC" / "Save PLC", or "PC -> PLC" / "PC <- PLC". Anything except Upload/Download.

They used to do it. Maybe it's the new batch of programmers that don't do hardware, have never programmed a PLC (or only used one brand) and code to spec.

Dave

Interesting question, Steve. I don't think any two vendors I've worked with do it the same way. AutomationDirect.com uses "Write program to PLC" and "Read Program from PLC". They also have those cute little PLC pictures with the arrow pointing into or away from the PLC.

The old Mitsubishi Medoc used a "Transfer" menu, with separate "MEDOC->PLC" and "PLC->MEDOC" items.

Cutler Hammer's GPC software is similar. Through the Online Menu you can use either a GPC ==> PLC or PLC ==> GPC item.

I dont understand how any of you can think of upload or download as wrong either way... the problem is, it is incomplete.

upload and download mean nothing if it isnt referenced to something. when transfering a file, both is going on, RS logix is uploading to the PLC, and the PLC is downloading the program. The same can be applied to store / load, read / write.

I havent used that many different software packages, but from what I have seen, they usually call it uploading / downloading / whatever in reference to the software package.

Regards,

Steve

Not that it matters, but I beg to disagree. In your example, RSLogix IS downloading to the PLC; the PLC is being download to. I think that's the premise behind rsdoran's posted definition.

Now, on to more pressing questions ... now where was I? Oh yes - is it the electrons that move or the holes that move? Hmmmm...