Best Printer Brand / Options for vDos Compatibility

[mikegieg]

Hello,

I plan to use vDos to run a DOS based POS system I wrote in Turbo Pascal back in the late 90's and need to source an printer to print invoices.

So if starting from scratch, which brand(s) of printer(s) is best for compatibility with vDos? My preference, if possible is to use vDos without any addons like DOSPRN. Though, I am open to this as well..

My initial preference is a HP Inkjet or HP Laserjet. However, I see where Inkjets may use PCL3GUI vs PCL3/6 for their Laserjets.

I have yet to dive into figuring out driver compatibility; only read the vDos Printer pdf, which mentions HP PCL.

As such, I am trying to find the path of least resistance and best vDos compatibility with a couple datapoints thus far:
- My Xerox network connected MFP does not automatically support legacy printer control codes sent via my POS program through vDos for obvious enough reasons.
- An Epson receipt printer TM=m50 seems to work well enough when using COM1 = tio:0 SEL:"EPSON TM-m50 Receipt" RAW. As expected, I think.
- A network attached Epson inkjet printer also seems to work well enough. Also as expected, I think?

Though, I would prefer a HP Inkjet or HP Laserjet, for the commercial POS application. Any suggestions as to what to stay away from vs purchase with little concern?

Many thanks!

[jamesb52]

This may not be what you're seeking, but it still might be useful information. My SharkBase (Clipper compatible) applications in vDOS can send output (receipts, invoices, etc) to a text file (C:\TXT\*.TXT) which I can then capture with a Windows PHP file which sends it to any convenient Windows printer. thereby skipping the DOS printer port. I've never bothered to format fonts, etc, because I can use the printouts just as they are. If your application can print or save to a text file, this could be a useful direction to take.

[mikegieg]

Thanks! Yeah, it's the need for a few font size/type control codes I use e.g. for a fine print section added to some invoices. This comment from HP, "PCL3GUI remains proprietary. HP uses it in the HP DeskJet series printers and DesignJet larger format printers (plotters)." from here (https://developers.hp.com/hp-printer-command-languages-pcl) is what has me wondering if I should avoid HP Inkjets and go with a HP Laserjet or an Epson Inkjet. My original codes control Okidata printers but I can change the codes to whatever. I just need to settle on what's hopefully the most compatible option(s).

[Jos]

The programs printer output is already saved by vDos to two text files named #<DOS printer port>.
That with the .ASC extension contains the ASCII output as-is, .TXT the converted to Unicode text.

vDos sends the original output (so including printer control codes) to the printer if you specify the RAW option.
Else the output is interpreted by vDos and send as formatted GDI pages to the printer (driver).

You could first print to a virtual PDF printer (no RAW option!) and verify the printout is to your likings.
If so, you can chose any printer supported by Windows. The printouts will be same, no matter what printer.

Jos

[mikegieg]

Ahhh. Thanks! This is most helpful! Then in the case of, "Else the output is interpreted by vDos", 'interpreted' looks to mean that vDos understands some printer control codes? Apologies if I should have understood this from the documentation. I just printed another test to my network attached Xerox printer using embedded Epson control codes and it looks to have worked! I use #27#103 to select 5cpi temporarily for my fine print and #27#80 to reselect 10cpi for the rest of the invoice.

Thus it would appear that the answer to my original question may be that I can use really any printer and corresponding driver as long as my code uses printer control codes understood and interpreted by vDos (e.g. Epson); since vDos sends a formatted GDI page..

Seems some of my original Okidata control codes might not have been interpreted, which threw me off track on what is possible..

Very excited now,
Mike

[Jos]

vDos recognizes many/most Epson/PCL/ProPrinter control codes used by DOS applications.
Mainly excluded are bitmap graphics (obsolete) and support of more than one font type.
Unsupported printer codes are ignored.

I don’t know where the supposed need for third party print processors comes from.
But some seem to insist on using one because once (NTVDM…) required that.
Or a license of that was bought, so it still has to be put to use?

Jos