Prevue Channel System Disk

Discuss the awesomeness of the Prevue Channel, Prevue Interactive, Prevue Networks/United Video Satellite Group, TV Guide Inc., etc. right here.
tin
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Re: Prevue Channel System Disk

Post by tin »

Interesting, I'll check it out if you get nowhere, but first more reverse engineering of the atari EPG.

A thought occured, I think the errors you get are because the genlock and audio switching cards are not present, the software will try and control them I guess.

We could do with an older version, perhaps starting with EPG Sr (for Amiga 1000 I believe?) although I'd also like to try on the the older EPG Sr style prevue guide, although I guess once more it will expect to find the genlock and audio cards. The most interesting thing would be to see if the EPG Sr works with the Atari data stream (I guess it must do)

Do you think your contact may be able to source older disks?
AriX
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Re: Prevue Channel System Disk

Post by AriX »

tin wrote:Interesting, I'll check it out if you get nowhere, but first more reverse engineering of the atari EPG.

A thought occured, I think the errors you get are because the genlock and audio switching cards are not present, the software will try and control them I guess.

We could do with an older version, perhaps starting with EPG Sr (for Amiga 1000 I believe?) although I'd also like to try on the the older EPG Sr style prevue guide, although I guess once more it will expect to find the genlock and audio cards. The most interesting thing would be to see if the EPG Sr works with the Atari data stream (I guess it must do)

Do you think your contact may be able to source older disks?
Right, keep me up to date on the reverse engineering of the EPG - maybe I'll see if I can learn some more Atari ASM, I'd love to try to figure this stuff out too.

Yes, the errors are because of the lack of hardware. I forgot to say that in my post.

Unfortunately at this point I really have no way of getting any sort of older software - he only has one disk, and I don't currently know anyone else with the software. I will have to start trying to find some more contacts and seeing if I can get any sort of other software build.

The thing about the data source is that the Atari EPG hardware includes a hardware demodulator that decodes the WGN feed with the data stream into a serial format directly to the Atari itself. It's possible that the Amigas also have some sort of hardware demodulator in some sort of card that decodes the Prevue feed into the same format, but it's also possible that the demodulation is done in hardware, in which case it would work a little differently. I'll contact some people and see what they know, but we'll definitely have to do some patching down the line in order to get the ESQ application to run without the genlock hardware. Alternatively, I believe this: http://cgi.ebay.com/NTSC-Video-Graphics ... _860wt_941 is a compatible genlock card, and we buy one, hook it up and see how it works. It may require the satellite card and other hardware too though.
Bolt96
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Re: Prevue Channel System Disk

Post by Bolt96 »

Hmm...interesting. I'd like to take this emulator for a spin myself. I saw on your latest video of the epg you were able to edit ads by typing a "!" on the scroll speed section. I've downloaded the rom file but how did you manage to get to the edit screen?
tin
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Re: Prevue Channel System Disk

Post by tin »

Reverse engineering coming on well. I can inject data as if it came in from serial, and I understand some of the basic commands enough that the software will act upon data injected. The pain is there's lots of checksums so I have to manually work them out at the moment, and I have no way yet of connecting a serial port to the emulator so I have to poke the bytes into memory by hand. Injecting listings appears MUCH more complicated, and I haven't seen anything yet to understand how to tell the program what it's custom channel list is, but work continues reasonably quickly and I will have a better understanding in a few days.

Regard learning assembly, I am pretty much most of the way there. I have annotated the vast majority of the dissasembly to understand it, and I'll release it when it's a bit more complete. It's funny I have been aware that there is such a thing as 6502 assembler for perhaps 20 years but never learned it or investigated how it works, it's all just a bunch of commands moving data around memory! I suppose that makes sense, just never thought of it like that. So the problem isn't really understanding what the code is doing, but more why it's doing it, and what was in the mind of the programmer of both the display and controlling software.

Also I am not quite sure yet how I will inject data to an emulator or a real atari/amiga via the serial port. I'm aware most emulators can use devices like SIO2PC to connect real atari serial peripherals to PC which might be of use. I have seen some program called com0com which can create virtual serial ports on a PC. I guess I can write a program to send data to one of them, it will go round in a loop into a second port, and hopefully I can set one of the emulators to use that port to recieve serial from. I haven't seen how to do that in an emulator yet. I've briefly researched some APIs for doing serial port access in Perl (I'll be writing the final data injector in Perl). If anyone has any ideas or fancies experimenting in this area it would be a massive help while I'm still disassembling.

@AriX, a shame about the software. I think we're a long way away from making the split screen version do anything useful. I will post on EAB to ask anyone who has older versiont to see if they'll share. If I can find my amiga.org account I will ask there too. I am certain there are a few people with prevue Amigas, just not sure if there'll be any EPG Sr disks left anywhere!

Regard your comments about the atari EPG over WGN, I am certain, reading the wikipedia article that the EPG Sr, and Prevue Guide both use the data in the same way. I think Atari EPG Jrs were still in operation a long time after the introduction of Amiga Prevue Guide, and it would make sense for the both to use the same data. The Jr code is written to ignore control codes it doesn't understand rather than crash :)

Again from the wiki, I am sure the Amiga 1000 EPG Sr appears to use a demodulator plugged into the serial port, I presume just like (or very similar) to the one inside the EPG Jr rackmount case. The Wiki article says the A2000 Prevue guide used a demodulator that does go inside the case, but only gets power from the slot, data is still demodulated and put out on an external serial port to go into the Amiga, just like the Jr and Sr. I am reasonably sure that once Prevue Guide began, the exact same data in the VBI of WGN will also have been there on the broadcast video from Prevue Guide HQ. Potentially they would have stopped broadcasting it on WGN and pointed the EPG Jrs and Srs satellite reciever to the prevue guide channel, even though they wouldn't show any of the video.

I am however sure that the Prevue Guide version will look for and need to see the genlock and audio switcher hardware at least, as the code will definitely control them both. I'll have to find one that I can buy and get imported to the UK!!
tin
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Re: Prevue Channel System Disk

Post by tin »

Bolt96 wrote:Hmm...interesting. I'd like to take this emulator for a spin myself. I saw on your latest video of the epg you were able to edit ads by typing a "!" on the scroll speed section. I've downloaded the rom file but how did you manage to get to the edit screen?
You enter the menu by pressing <ESC>. I have noted that (on windows) Atari800win works, while Altirra doesn't - it doesn't recognise the <ESC>
AriX
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Re: Prevue Channel System Disk

Post by AriX »

Bolt96 wrote:Hmm...interesting. I'd like to take this emulator for a spin myself. I saw on your latest video of the epg you were able to edit ads by typing a "!" on the scroll speed section. I've downloaded the rom file but how did you manage to get to the edit screen?
Right, maybe I should write a tutorial for interested people on how to get it up and running in an emulator - it's not the easiest thing to figure out if you've never used an Atari before (since they posted like 4 different versions of the ROM to use :p)
tin wrote:Also I am not quite sure yet how I will inject data to an emulator or a real atari/amiga via the serial port. I'm aware most emulators can use devices like SIO2PC to connect real atari serial peripherals to PC which might be of use. I have seen some program called com0com which can create virtual serial ports on a PC. I guess I can write a program to send data to one of them, it will go round in a loop into a second port, and hopefully I can set one of the emulators to use that port to recieve serial from. I haven't seen how to do that in an emulator yet. I've briefly researched some APIs for doing serial port access in Perl (I'll be writing the final data injector in Perl). If anyone has any ideas or fancies experimenting in this area it would be a massive help while I'm still disassembling.
Right, I'm more of a Mac guy myself, so I don't know much about Windows, but SIO2PC + com0com sounds like a pretty roundabout way to do what you're trying to accomplish. I'm not sure, as I haven't looked into it much, but I would be surprised if there wasn't a way to directly input stuff into a fake serial port without having to emulate a real one. I'll take a look into this.
tin wrote:@AriX, a shame about the software. I think we're a long way away from making the split screen version do anything useful. I will post on EAB to ask anyone who has older versiont to see if they'll share. If I can find my amiga.org account I will ask there too. I am certain there are a few people with prevue Amigas, just not sure if there'll be any EPG Sr disks left anywhere!
I really don't think you're going to get very far on EAB. Amiga.org may be more successful (I have already contacted all of the people on that forum that have said they've had Prevue Amigas in the past... Only one of them has responded so far, and he's the one who gave me the floppy disk. I could be wrong, but my impression is that most of the people who do have Prevue Amiga units do not have any software with them, unless maybe UVSG used hard drives for some of the units instead of floppies). It couldn't hurt to post on Amiga.org (or maybe I'll do it). This stuff is hard to find - after several months of searching, I was surprised I was actually able to get any of this software, and frankly it could be a while before we get another different copy.

I also have talked to someone on AtariAge.org about his EPG Jr. unit, but he does not want to sell it except for an insane price (he did not specify, just said he wouldn't sell it unless I was offering a whole lot of $$)

Additionally, I talked to the original eBay seller who sold these EPG Jrs, who says that he has a few more of them that had dead power supplies and don't come with the cool blue cases. He didn't tell me whether or not he had the demodulators that came with them, and even though I told him I'd be interested in purchasing one, he has not gotten back to me in in several weeks. I sent him another message two days ago, and he still has not gotten back. Maybe I'll try to find an alternative way of contacting him.

On top of that, I talked to a cable supply company who used to sell refurbished EPG Jr. units at least until 2006, who thinks that they will be able to sell me one (I don't understand what that means or whether or not they have them, this is just what they told me). I'll see if I can buy one from them, and see if they have any Prevue or EPG Sr units as well.

I will keep doing research into this and try to build up my amount of contacts who have worked at UVSG and who have had these units and see if I can get any more software or hardware.
tin wrote:Regard your comments about the atari EPG over WGN, I am certain, reading the wikipedia article that the EPG Sr, and Prevue Guide both use the data in the same way. I think Atari EPG Jrs were still in operation a long time after the introduction of Amiga Prevue Guide, and it would make sense for the both to use the same data. The Jr code is written to ignore control codes it doesn't understand rather than crash :)

Again from the wiki, I am sure the Amiga 1000 EPG Sr appears to use a demodulator plugged into the serial port, I presume just like (or very similar) to the one inside the EPG Jr rackmount case. The Wiki article says the A2000 Prevue guide used a demodulator that does go inside the case, but only gets power from the slot, data is still demodulated and put out on an external serial port to go into the Amiga, just like the Jr and Sr. I am reasonably sure that once Prevue Guide began, the exact same data in the VBI of WGN will also have been there on the broadcast video from Prevue Guide HQ. Potentially they would have stopped broadcasting it on WGN and pointed the EPG Jrs and Srs satellite reciever to the prevue guide channel, even though they wouldn't show any of the video.
Right, I wasn't suggesting they used the data in a different way or used different data... I was just concerned the demodulation was being done in software. However, you're absolutely right, it must have been done in the hardware, so they do use the same data input. :)

They actually broadcast it on WGN until 2005. During the Prevue days, they kept it going on WGN just as a convenience for cable companies who already had it set up that way - they didn't have to get a special satellite setup for the Prevue feed just to keep their old EPG channels going. It would work fine, however, to hook up an EPG channel to a Prevue C-band feed if they were to do it that way. The Prevue feed had the exact same listings information as the WGN feed, plus some extra information (that, as you said, the EPG machines would just ignore).
tin
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Re: Prevue Channel System Disk

Post by tin »

Aha, with your contacts you're obviously getting better info than me, I am just guessing from the info on Wikipedia.

I've posted a message on EAB, will see what I get. I searched for Prevue info on Amiga.org and I didn't see much, I guess you PMed everyone, a more general post may be worth a go if you fancy.

I am certainly interested in buying kit, if you get offers of more than one or kit you aren't interested in pls let me know.
AriX
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Re: Prevue Channel System Disk

Post by AriX »

tin wrote:BTW i doubt the disk could update itself because of the amount of data needed to go through the air (although reverse engineering will reveal) so we could do with getting hold of older ones if by any chance they still exist.
Just realized the other reason why I thought the Amigas would update themselves over satellite. One of my contacts (who I just messaged asking if he knew of the whereabouts of any older versions of the software) is an ex-UVSG employee who worked there for the last few years of Prevue and for the first year or so of TV Guide. This is a direct quote from him:

"At that time, the Amigas were updated via satellite. I don't work there anymore, but I'm relatively sure that the new PC platform is updated via the Internet now."

Also, there's a folder on the TV Guide ADF about "Update". I haven't looked into it much.

This is bad news for us. It means it will be VERY VERY hard to get an older version of the software, since it was overwritten every time. I don't know if they preserve historical copies of Prevue software for some reason over at Lionsgate, but I do have one person's contact information who is high up over there, so maybe I'll give that a try. Another possibility is that we could locate an EPG Sr. unit, since (most of) those units would not have been upgraded to any sort of Prevue software... However, these are probably rarer than the Prevue units, since they were phased out long before for the most part (presumably).
AriX
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Re: Prevue Channel System Disk

Post by AriX »

tin wrote:Aha, with your contacts you're obviously getting better info than me, I am just guessing from the info on Wikipedia.
Most of the technical information on Wikipedia was posted by my (internet) friend Steve who was a consultant for TV Guide Inc. briefly in 1999 when they were switching from the Amiga platform to Windows NT-based machines... He explained a lot of it to me in depth in some emails back.
tin wrote:I am certainly interested in buying kit, if you get offers of more than one or kit you aren't interested in pls let me know.
Sounds good :)
AriX
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Re: Prevue Channel System Disk

Post by AriX »

(Sorry for the triple post, I guess no one will yell at me on my own forum :p)

By the way, tin, I don't know if the serial input you're talking about that the EPG reads from is an R: patch, but at least on my Atari800MacX emulator, you can set a network port to input directly into there, so you can just telnet to localhost and put stuff in.
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