Setting up a PC-based monitor tester

[McMurdo]

I have a multi-standard vintage ISA bus VGA card here with a 9-pin RGB TTL and 15-pin analogue output. The DOS utility (!) that came with it on 5.25in floppy (!!) allows the card to output all standard PC formats from one or other of the sockets including Hercules, MDA, CGA, EGA, VGA, RGB ttl, RGB+I, etc. at various fixed resolutions and frequencies using a combination of software 'switches' and hardware DIP switches on the rear. It will also down convert PC applications for composite video on BNC.

In a nutshell, can I set up something for my modern PC that will do a similar thing? I currently use a vintage PC just for this old card and would like to incorporate it into something more modern.

[Chaparal]

Hi Kevin,

try this one, works under windows xx


Peter

[McMurdo]

Thanks Peter, but this one doesn't allow control of resolutions & frequencies?

I need fairly free control of the display standards particularly slow-scan down to TV rates.

[PaulM]

Try 'Powerstrip'. I've used it for all sorts of things and it doesn't seem to muck up your PC - you can always 'go back'.

See: http://www.entechtaiwan.com/util/ps.shtm

Cheers,

Paul M

[cmjones01]

I second the vote for Powerstrip. I used to use it to drive a 625-line monitor straight from the VGA connector to its SCART socket, and the resolution and interlacing all seemed to work very nicely. The configuration was very tweakable - my 625-line interlaced 50Hz mode was hand-made by me. It was good enough that I paid the registration fee. It also supports hot keys so you can quickly flip from one resolution to another.

Chris

[neon indicator]

I looked at it once, but my current nvidia driver on XP for GT210 allows all that built in.
Except no hot key resolution switching that works sensibly.

[McMurdo]

I need to install a second video card for testing I think because my normal LCD keeps saying 'frequency out of range' when I alter anything on Powerstrip. As it will, of course!

I wonder if I can select 8-bit colour and then make some sort of analogue to TTL adapter so that my Nvidia card will drive these old monitors. Various of these old monitors use either +ve or -ve H or V sync, or a combination of the two, some use composite sync, some seperate etc. I have a usb-powered box I made up some time ago to either invert or combine syncs off the HD15 outlet, I think I need to make another to level-shift!

[neon indicator]

8 bit colour is no help

[techiesteve]

Kevin, I know how useful what you are seeking is. Years back when I repaired monitors for a living we used a DOS based Viewsonic utility that allowed selection of resolution and refresh rate via function keys, and displayed an excellent range of test patterns. It only supported Trident ISA cards. A better utility was supplied by Radius for their apple based NuBus cards, I used under OS 7 running on IICX and IICi's. I've never since seen software so versatile, only a programmable video generator was more versatile but they were expensive.

[McMurdo]

8 bit colour is no help

Can you suggest anything

[Kat Manton]

Hi,

First, please note that I have absolutely zero useful knowledge these days where Windows is concerned. The last version I really used was '95 and I haven't used any version in nearly a decade now.

However, I've managed to get everything including the 180-line pre-war German standard, via Baird 240-line, 405, CBS field-sequential, 819, various resolutions needed for old fixed-rate Unix workstation monitors and so on from certain AGP nVidia cards. So IMO there should be no problem getting timings (with any sync polarity) required for any other monitor out of such a card.

PCI versions of such cards were also available. So you could set up a dual-head Linux box with the desktop on one head (AGP or on-board) and the other head (PCI) used solely for odd resolutions and displaying test patterns. Linux won't spread the desktop over both heads unless you configure it to, and in this case you probably don't want that.

TTL monitors could, I think, be driven with a level-shifter; I'd be using fast comparators for that (and probably have a pot to tweak the threshold.) I reckon the 'I' signal needed for RGBI monitors could also be generated using comparators. The output would probably be practically unusable for desktop+applications, but if you're only directing the output of one application displaying full-screen test patterns to the secondary display, that won't matter. Plus the test patterns could be tailored for your analogue-to-TTL converter.

Another option would be to assemble a somewhat more recent PC. I have a couple or three boards with AGP, PCI and ISA slots which will comfortably run a current Linux distro. Dual 733 MHz PIII, 1.3 GHz Athlon, that sort of thing. (I'm keeping them because they'll comfortably run Linux and have ISA slots.)

I doubt Linux would support your old ISA card (it might, it shouldn't entirely be ruled out.) But DOSEMU can be configured to allow direct hardware access to certain ports, memory ranges, etc. Assuming your ISA card doesn't conflict with anything, you could run your DOS application under DOSEMU on Linux and continue to use your old ISA card.

Kat

[McMurdo]

I was hoping to ditch the old ISA card and incorporate something running a DOS 16-colour test programme on XP through a command window and a modern AGP card such as this nvidia I have in my PC here.

As far as writing an application for it is concerned, I'm all at sea. I trained on an RML 480Z....

[dragonser]

Hi,
I don't know if anyone has thought about making up a hardware device like the 405 line test card generator that was also mentioned here ?
I think the link was http://www.thevalvepage.com/projects...d/testcard.htm
I know that when one company I worked for needed to repair some non standard monitors [ 24khz anyone ! ] one of the people there designed something similar [ back in 2000 ] to the eprom based 405 line test card generator [ but with I think a faster clock ].
this worked well if you only want to test one type of monitor., and can work out the timing of the video and sync signals.

[neon indicator]

Originally Posted by McMurdo

I was hoping to ditch the old ISA card and incorporate something running a DOS 16-colour test programme on XP through a command window and a modern AGP card such as this nvidia I have in my PC here.

As far as writing an application for it is concerned, I'm all at sea. I trained on an RML 480Z....

I'd use something a bit more modern than an AGP card.

A DOS program (even full screen) will only do standard modes, not custom modes running in XP.

Better than NT's own DOS virtual Machine for DOS is http://www.dosbox.com/
(same as used on Symbian, Linux and other OS). It runs all the old DOS games. It might even do custom modes full screen.

the GT210 (and other modern) Nvidia card has good utilities on XP to set ANY timing... A DOS program has to be "full screen" and depends on what emulation you are using as to if that is any use.

Really if you want to run DOS program that does non-standard modes you need to use an old PC and DOS. Running any kind of emulator for DOS on Linux or NT (and that is the ONLY way to run DOS programs, a NT console program or Linux console program is not using the same environment as a DOS program). In DOS Emulator (on Linux or NT) I can run CGA / EGA / VGA mode DOS games, but the "real" output is still 1600x 1200 or 1024 x 768 or 1920x1080, what ever the Host OS mode really is.

So you either "really" use DOS on an old ISA machine or do new SW for Linux X windows or NT GUI (win 2K, XP, vista and Win7 are versions of NT, which I've been using since 3.5 and has NO connection with Win'98, 95, ME or win3.11 etc).

With Linux there are documented command line utilities so set mode, but not all GFX cards do all modes. With NT you need Powerstrip, AMD driver or Nvidia drive that lets you create custom mode and suitable GFX card.

Converting from VGA to TTL can be done with a suitable comparators (one that's fast enough). RGBI TTL can have the I channel driven by adding RG&B with resistors and a 4th comparator. You might even get away with 2x 7414

It's simpler to stick with what you have.
Getting replacement ISA 486 PCs is easy for DOS.

(Was the RML 480Z the black shoe box with ribbon cable on top instead of a backplane? We used to mod those "Shoe boxes" for Graphic printing on MX80. RM had only wired 7 bit centronics!)

[McMurdo]

The big problem with what I have is that alot of the frequencies have to be set via dipswitches on the card. Changing the switches involves a power-down and reboot, so if we get a monitor for test with unknown frequencies, it can be very tedious running through all the suspects by continually changing switches and power-cycling the PC. I thought a software based system would be more elegant.
Some of the monitors we get are industrial units that have their own standards such as 19khz / 58hz on a greenscreen mono TTL with composite sync and others such as RGBI+H+V colour at RS422 line drive 16.8khz/60hz ...etc
The electrical part I can sort but the PC bit is the elegant though elusive bit I seek!

[neon indicator]

Well, VGA to TTL is easy.

You can create and save custom resolutions on Linux and XP. It's a matter of a suitable modern card that does all the modes. I Just checked the GT210 on XP with nvidia driver and it can do true 640x350 in 525 line 60Hz progressive. Also 1024 x 576 50Hz progressive (both work on my Multisync VGA screen). It does 1024 x 768 @ 43Hz interlace too. It lets me create the timings for 405i, 525i and 625i but claims the Monitor doesn't support it.

So you need VGA to whatever HW adapators and suitable modern PCI-e card and drivers for XP or Linux. You don't need your existing DOS programs, just create appropriate images and slide show.

You can use a Drawing / paint / graphics program to create the text cards for each resolution and use the "readily available" slide show utilities free on XP or Linux. So no DOS program needed.

[Kat Manton]

Originally Posted by neon indicator

Running any kind of emulator for DOS on Linux or NT (and that is the ONLY way to run DOS programs, a NT console program or Linux console program is not using the same environment as a DOS program). In DOS Emulator (on Linux or NT) I can run CGA / EGA / VGA mode DOS games, but the "real" output is still 1600x 1200 or 1024 x 768 or 1920x1080, what ever the Host OS mode really is.

I believe you're confusing DOSBox with DOSEMU. I'm unfamiliar with DOSBox, but it appears to perform emulation in a somewhat different way. DOSEMU only runs on x86 Linux systems, not NT. Which DOS runs on DOSBox? DOSEMU comes with FreeDOS but MS-DOS 6.22 or whatever could be installed if an app. required a specific version. Running DOS programs on DOS on virtualised hardware is pretty close to running DOS programs on DOS on real hardware. Plus it can be configured to allow access to real hardware, like, say, an ISA graphics card; which is what I was suggesting.

But that's academic; Kevin would prefer to use more modern hardware. I'm still not sure how you'd manage with a single-head system; I've seen KDE on a 405-line TV set and it's neither pretty nor usable. I'd be looking at a dual-head setup with the desktop confined to one display and the other used solely for displaying test patterns at odd resolutions. It's very similar to a system I'm setting up at present so it's definitely possible; it would just need the list of modes changing.

I've no idea how you'd do anything like this on Windows; so I bow to your superior knowledge. I found it frustratingly restrictive and abandoned it years ago. For all I know it may have improved.

Kat

[neon indicator]

I have no experience of DOSEMU, so I can't confuse the two.

DOSbox 0.72 appears to have a builtin clone of DOS 5.0 It Loads win3.1 in 1.5s on a P4 Mobile 1.8GHz

Well, Win95 wasn't Windows Kat, it was DOS + GUI. I was using NT since 1994. As well as UNIX since 1986, and Linux since 1998. Win7 isn't as "good" and stable as NT3.51, but that's progress. I must say the last few Linux (particularly Ubuntu) have improved for old PCs due to supporting low end Netbooks better. I've used Centos, Unbuntu, Barack, Redhat, Fedora, Suse, "vanilla" Debian (x86 and ARM), Ubuntu, Gentoo, OpenWRT, DDWRT, various "commercial" embedded (Cisco, Motorola, RealMultimedia, Lyngbox) Puppy and DSL. I've done Console programming in C on Linux/ Unix since 1986, Java, C & C++ X-windows on Linux since 1999.

I never did any programming for Win3.1 / Win3.11 / Win95 / 98/ ME as these are rubbish environments. You can't create a named pipe on them, only connect to one over the network.

Dual head is fairly easy on NT or Linux. I'd use the motherboard VGA / HDMI/DVI for the "control" screen and use a suitable PCI-e graphics card with VGA and external TTL converter for the "testing". Which sounds more like EGA type graphics than 405.

Not many people are expert on NT, most people are "appliance users", so for someone that isn't an expert the Linux route may be better as there is more support. Of course 10 years ago every Linux user was an expert and now the majority are no more expert than Windows users so the Forums have a lot of chaff.

You and I are endangered species Kat.

[neon indicator]

DOSbox (which is not needed for this project) runs on

Windows 0.74 Win32 installer
FreeBSD package 0.74 TBZ
Fedora 0.74 rpm
Gentoo Linux 0.74 portage
Source 0.74 Source
Mac OS X 0.74 dmg (Universal)
RISC OS 0.74 zip
Debian 0.74 deb
Solaris 10 - sparc 0.73 pkg
OS/2 0.72 exe (OS2)
BeOS 0.63 binary (x86)

It allows non x86 host to run X86 code.
http://www.dosbox.com/download.php?main=1

[Kat Manton]

Ah, okay; I think that clears that up; DOSbox emulates a computer running DOS, DOSEMU is more like a (specialised) virtual machine developed to actually run versions of DOS.

The 'allowing direct access to hardware' thing would be useful if one had a specialised card which wasn't ever supported on Linux or Windows but which came with DOS software. One could then use the card and original software. Worth bearing in mind if you ever needed it; I know there are some old bits of (typically) industrial hardware/software which some people still need to use; DOSEMU would let you do that. I use it for OrCAD, the software for my ancient EPROM programmer and a few assemblers/disassemblers/compilers/etc. for which there are no Linux equivalents. I just haven't needed to look at DOSBox as everything I've tried works with DOSEMU.

The relevance here is it would allow the ISA card and original DOS utility to be used, if that was a suitable solution to the problem

Kat