HP-41 and video interface 82163a / 92198a

[Vincent Weber]

Sorry JF I answered you on the wrong thread. Here it is:

Thanks JF.
I tried to use the video display in Emu41 and I have the following questions:
1/it seems that neither 32 nor 80 column are emulated, but 40.
Why ?
2/it seems that video inverse characters and cursor blinking is not emulated. why ? Is it what you mean by "partially emulated" for the escape sequences in Emu41 doc ?
3/what is the use of emulating the 82143a printer over emulating the video interface since you don't emulate the graphics ? To get a longer "paper" ? But I have not found how to control the paper length, nor how to scroll it...
4/why not emulating the 82162a printer ? Can you confirm that its new FMT instruction is dedicated to it and cannot be used with the video interface ?
5/you say in emu41 doc that the escape sequences "are not used with the hp-41, except with the paname rom". Can you confirm that you are not aware of significant applications that would make use of these features ?

Thanks in advance and regards

[J-F Garnier]

(05-20-2015 12:46 PM)Vincent Weber Wrote:  I tried to use the video display in Emu41 and I have the following questions:
1/it seems that neither 32 nor 80 column are emulated, but 40. Why ?
2/it seems that video inverse characters and cursor blinking is not emulated. why ?
3/what is the use of emulating the 82143a printer over emulating the video interface since you don't emulate the graphics ?
4/why not emulating the 82162a printer ?
5/Can you confirm that you are not aware of significant applications that would make use of these features ?

Hi Vincent,
That's a lot of "why".
To make it short, the answer could be "because", or "why not".
Because I did it in that way more than 15 years ago.

Seriously, some answers about Emu41:
1/ I restricted the screen width to 40 columns because I wanted to keep half the screen for a key mapping help, and I wasn't trying to emulate a particular HP device.
2/ 3/ 4/ because ... Emu41 was (still is) a text-mode DOS application. No graphic. However, blinking cursor and cursor types are emulated.
5/ Yes, I don't know any serious HP-41C application using the video escape sequences.

J-F

[Vincent Weber]

Thanks JF. Could you just tell me what escape sequences are not emulated in emu41 ? Video inverse characters ? Since you said "partially emulated", I'm just curious about the non emulated features...

[Christoph Giesselink]

(05-20-2015 10:55 PM)Vincent Weber Wrote:  Thanks JF. Could you just tell me what escape sequences are not emulated in emu41 ? Video inverse characters ? Since you said "partially emulated", I'm just curious about the non emulated features...

Hi Vincent,

you may have a look at the Emu41 sources. Function disp_char() in file USERPC.C implements the supported ESC sequences.

Christoph

[Vincent Weber]

Thanks Christoph. From the source code I conclude that the escape sequences have been implemented in full, not partially. But that the reverse video characters are not implemented, as they are 8-bit (>=128) and the code just displays "." for > 127. Am I correct ? Btw this also seems the case for emu71 (dos) since the examples on the web page at the bottom shows reverse video for your windows implementation but not for dos...

[J-F Garnier]

(05-21-2015 09:10 AM)Vincent Weber Wrote:  From the source code I conclude that the escape sequences have been implemented in full, not partially.

Not exactly. The page scrolling escape sequence (Esc S/T) are not implemented (because my DOS emulators are using a single video page) as well as the Esc L/M/Y/Z and other non-HP Esc extensions found in the Mountain Computer MC00701A (aka 92198a).

Quote:But that the reverse video characters are not implemented, as they are 8-bit (>=128) and the code just displays "." for > 127. Am I correct ? Btw this also seems the case for emu71 (dos) since the examples on the web page at the bottom shows reverse video for your windows implementation but not for dos...

Yes, no inverse video support on my DOS emulators. Frankly, this has never been an issue for me (well, except maybe with the HP-75C that uses such inverse characters).
Contrary to Christoph's excellent work, I never targeted full compliance with the original equipments, just a high level of compatibility.

J-F

[Vincent Weber]

(05-21-2015 04:49 PM)J-F Garnier Wrote:  

(05-21-2015 09:10 AM)Vincent Weber Wrote:  From the source code I conclude that the escape sequences have been implemented in full, not partially.

Not exactly. The page scrolling escape sequence (Esc S/T) are not implemented (because my DOS emulators are using a single video page) as well as the Esc L/M/Y/Z and other non-HP Esc extensions found in the Mountain Computer MC00701A (aka 92198a).

Quote:But that the reverse video characters are not implemented, as they are 8-bit (>=128) and the code just displays "." for > 127. Am I correct ? Btw this also seems the case for emu71 (dos) since the examples on the web page at the bottom shows reverse video for your windows implementation but not for dos...

Yes, no inverse video support on my DOS emulators. Frankly, this has never been an issue for me (well, except maybe with the HP-75C that uses such inverse characters).
Contrary to Christoph's excellent work, I never targeted full compliance with the original equipments, just a high level of compatibility.

J-F

Thanks a lot JF for this precise answer.

One thiing I don't understand is why you provided HP82143a emulation: since you don't provide graphics mode, and no scrolling (singe page video mode you said), so you can't scroll the "paper" as well I imagine? What does the 82143a possibly add to the video interface emulation then ?

Lastely, could you confirm that the FMT (format) instruction of the 82162a HP-IL printer does not apply to the video interface, as it seems from both the HP-IL manual and the 82163a manual ? Maybe because to center text you need to know in advance the number of columns you have, which may not be the case with the video interface(s) ?

Many thanks and best regards

[Garth Wilson]

There's a Mountain Computer MC00701A 80-column HP-IL video adapter, with manual and power supply, on the big auction site right now. (It's not mine. I'm not involved.) Search for:

HP 41C 71C Mountain Computer MC00701A HP-IL Video Interface

I'm pretty sure it's the same thing as the HP92198 because "MC00701" is the HP-IL device identifier I use to find the HP-IL address of my own HP92198 with my HP-41cx or 71B. The manual looks identical to mine also. Can someone confirm that it's the same model? Which number was used first? When and why was there a change? The price at the moment is only $10 (with one bid), but mine works fine and I definitely don't need a second one sitting around.

Mine has two EPROMs in it. As you may know, EPROMs were only guaranteed to hold their data for something like ten years (although I've never seen one go down, even after 20-30 years); but I refreshed mine and kept copies of the images (in Intel Hex format) in case anyone else needed them to re-program theirs. I need to get that up on my website, but I just haven't done it yet. One of the EPROMs has the character generator info, so you could change that one and make your own character set if you wanted to. It would not be hard at all, assuming your EPROM programmer has a binary edit mode. You could have more than one and change them out, or stack them in a jury-rigged socket (there's plenty of vertical room) and use a switch on the chip-enable lines to select which EPROM to use. Another way would be to use a denser EPROM and have the switch change the state of one or more of the higher address lines, to select which character set to use.

My 92198 sat in the closet unused for many years, but since one of my oscilloscopes on the work bench went down recently and I couldn't get it fixed, I got the 92198 back out and filled the spot on the workbench with it and have used it a few times recently again.

FWIW, my ebay identifier is wilsonmines. (I think we're supposed to include that in posts if we talk about ebay.) Again, I have no part in this sale. The notice about it came up in my emails and I hope it goes to a good home where it will be valued and used.

[rprosperi]

(04-23-2017 08:24 AM)Garth Wilson Wrote:  Can someone confirm that it's the same model? Which number was used first? When and why was there a change?

Mountain Computer developed it and initially released it under their brand, but it was better than the 32-column model HP initially introduced, so HP acquired the rights to re-brand it and sell it as an HP Product, similar to the way they acquired/sold the AMPI STATS ROM for the 71B.

I never owned one, so not sure if HP printed their own manual, but I would guess not; the AMPI STATS ROM was sold by HP with the original AMPI manual which had only AMPI Copyright. I have seen many Mountain Computer Manuals, but never an HP Manual, for this device.

I also don't know if Mountain continued to sell it under their own brand once HP acquired it, but I'd guess not.

[Mark Hardman]

Not trying to hijack the thread. I recently acquired a Mountain Computer HP-IL video interface but have no composite monitor. Does anyone have any experience using an RCA composite to HMDI converter for connecting this interface to a modern computer monitor? Something along the lines of this?

Mark Hardman

[Garth Wilson]

(04-23-2017 01:06 PM)rprosperi Wrote:  I also don't know if Mountain continued to sell it under their own brand once HP acquired it, but I'd guess not.

Mine says on it, "Made exclusively for Hewlett-Packard Co. by Mountain," and "HP92198 HP-IL 80-column video interface" on it. I use it with a Zenith amber monochrome monitor.

[rprosperi]

(04-23-2017 07:17 PM)Garth Wilson Wrote:  Mine says on it, "Made exclusively for Hewlett-Packard Co. by Mountain," and "HP92198 HP-IL 80-column video interface" on it. I use it with a Zenith amber monochrome monitor.

Thanks for confirming so Garth, I couldn't imagine HP would get a non-exclusive license. If it's easy, could you post of pic of the HP branding? Interesting to compare it with the MC version in the listing.

[Sylvain Cote]

(04-23-2017 01:06 PM)rprosperi Wrote:  I never owned one, so not sure if HP printed their own manual, but I would guess not;
the AMPI STATS ROM was sold by HP with the original AMPI manual which had only AMPI Copyright.
I have seen many Mountain Computer Manuals, but never an HP Manual, for this device.

I have both the MC and HP versions of the video interface with manuals and the differences are ...

• adapter plug in the unit are different
• front sticker on the unit have different branding
• HP reformatted the manual but the information in it is the same
  

Sylvain

MC00701A Owner's Manual
HP-92198 Owner's Manual (search "92198 HP-IL 80 Column Video Interface Owner's Manual" on google)

edit: add manuals links

[Gene]

For the record, that is not my Othello program - It is Valentin's and came from PPC Journal or the games solution books.

Angel Martin put a version of it into the FUNSTUFF rom for the 41 which can be loaded into i41cx+.

[rprosperi]

(04-23-2017 08:56 PM)Sylvain Cote Wrote:  I have both the MC and HP versions of the video interface with manuals and the differences are ...

• adapter plug in the unit are different
• front sticker on the unit have different branding
• HP reformatted the manual but the information in it is the same
  

I could have predicted this... owning both that is...

(04-23-2017 08:56 PM)Sylvain Cote Wrote:  HP-92198 Owner's Manual (search "92198 HP-IL 80 Column Video Interface Owner's Manual" on google)

Although searching this on Google did produce some interesting pages, there were none with this manual, unless Google is acting differently in Canada

[Sylvain Cote]

(04-23-2017 10:36 PM)rprosperi Wrote:  

(04-23-2017 08:56 PM)Sylvain Cote Wrote:  HP-92198 Owner's Manual (search "92198 HP-IL 80 Column Video Interface Owner's Manual" on google)

Although searching this on Google did produce some interesting pages, there were none with this manual, unless Google is acting differently in Canada

I am surprised, normally it is the other way around. OK then, the HP manual is available at TOS.

[Dave Frederickson]

(04-23-2017 05:45 PM)Mark Hardman Wrote:  Not trying to hijack the thread. I recently acquired a Mountain Computer HP-IL video interface but have no composite monitor. Does anyone have any experience using an RCA composite to HMDI converter for connecting this interface to a modern computer monitor? Something along the lines of this?

I tried connecting the interface to the composite input on my monitor but experienced a lot of jitter. Marcus suggested I try a vintage monitor and that did the trick. I suspect that modern composite interfaces have a higher input bandwidth than the vintage CRT monitors. I would think that some sort of filter would eliminate the higher frequencies that are causing the jitter, but was unsuccessful finding something.

In related information, the HP 82912A and 82913A monitors are rebranded NEC monitors. The 9" monitor is an NEC JB-902M and the 12" is a JB-1201M.

Regarding the one on eBay, the price won't stay at $10 for long. These usually go for over $500.

I have the 92198 with the manual supplement for the 71, which seems to be missing from the document archives.

Dave

[Garth Wilson]

(04-23-2017 08:42 PM)rprosperi Wrote:  

(04-23-2017 07:17 PM)Garth Wilson Wrote:  Mine says on it, "Made exclusively for Hewlett-Packard Co. by Mountain," and "HP92198 HP-IL 80-column video interface" on it. I use it with a Zenith amber monochrome monitor.

Thanks for confirming so Garth, I couldn't imagine HP would get a non-exclusive license. If it's easy, could you post of pic of the HP branding? Interesting to compare it with the MC version in the listing.

Here's the label. (If you want a better picture, I'll have to wait 'til daylight.)
   

Here's a picture I took last week of the Zenith monitor displaying data from the HP-41 coming through the HP92198:

   

Darn. The pictures are not showing in the preview. Let's see if they show in the post. If they don't, suggestions as to what the problem is are welcome.

[Garth Wilson]

Here are the front and back covers of the manual:

   

[rprosperi]

(04-24-2017 05:02 AM)Garth Wilson Wrote:  Here's the label. (If you want a better picture, I'll have to wait 'til daylight.)

No, this pic is just fine, I was just curious how the branding differed.

Thanks for the pics!