)AP2000
Re: AP2000
Got a bunch of pictures, will post them tomorrow (although you guys seem to be busy with more important things than hardware that hasn't been used in 11 years )
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nwgatwcfan
- Posts: 115
- Joined: Mon Jul 05, 2010 5:52 pm
Re: AP2000
I'm still following along. It's been crazy busy at work and I have been ou of town the last few weekends....
Could the bottom connector be for a small tv monitor that a cable operator would use without having to unhook the top cables to see what the software was doing or it might be a passthrough. I think I remember on some previous photos elsewhere on the web that a small coax cable connected two of those connectors.
It's funny that it would only send a black and white image...
Keep us posted on this development. Can't wait to see the photos..
Thanks,
Steven
Could the bottom connector be for a small tv monitor that a cable operator would use without having to unhook the top cables to see what the software was doing or it might be a passthrough. I think I remember on some previous photos elsewhere on the web that a small coax cable connected two of those connectors.
It's funny that it would only send a black and white image...
Keep us posted on this development. Can't wait to see the photos..
Thanks,
Steven
Re: AP2000
That's a good point! It could have been used as a monitor, perhaps. The only thing is that the Amiga does have two other video outputs, a 25-pin one and an RCA connector - I would have expected they could use one of those, but the disadvantage is that they won't show the final genlocked output. Then again, neither does this odd black-and-white port on the bottom... Another weird thing is that the RCA connector seems to yield the same black-and-white picture. Maybe some sort of on-board video thing on my Amiga is broken? I have no idea.nwgatwcfan wrote:Could the bottom connector be for a small tv monitor that a cable operator would use without having to unhook the top cables to see what the software was doing or it might be a passthrough. I think I remember on some previous photos elsewhere on the web that a small coax cable connected two of those connectors.
It's funny that it would only send a black and white image...
Keep us posted on this development. Can't wait to see the photos..
The small coax cable that acts as a jumper between the baseband and audio switcher cards was included.
Re: AP2000
Video out on Amiga 2000 (on the RCA) is black and white. I am not sure why but I have assumed the reason is the expense of the components. They didn't introduce colour video out until the A600/A1200 (and probably the A4000 I guess). Of course a proper monitor is colour, or you could get a modulator to create a colour composite signal, but the genlock is often better than a modulator anyway. Interesting about the 3rd port. I wonder if it port just duplicates the RCA video output? Maybe 
I am following your events AriX, just not much to add at the moment
I am following your events AriX, just not much to add at the moment
Re: AP2000
http://www.flickr.com/photos/arixr/sets ... 011334814/
Here are the pictures I took last night - need to explain a few things when I get a chance about the control data light and maybe some other things.
Here are the pictures I took last night - need to explain a few things when I get a chance about the control data light and maybe some other things.
Re: AP2000
Nice
Can I ask a favour? Can you take a single high resolution photo of each side of the 3 cards and post them on your flickr? I am trying to reverse engineer any kind of bus communication.
<edit> From what I can see, ISA bus pins 6, 8 and 15 are connected to each other between the cards (the other pins are voltages and ground). They are even labelled 6 8 and 15 on the audio card. According to what I know there's no reason for this other than inter-ISAcard communication....
Can I ask a favour? Can you take a single high resolution photo of each side of the 3 cards and post them on your flickr? I am trying to reverse engineer any kind of bus communication.
<edit> From what I can see, ISA bus pins 6, 8 and 15 are connected to each other between the cards (the other pins are voltages and ground). They are even labelled 6 8 and 15 on the audio card. According to what I know there's no reason for this other than inter-ISAcard communication....
Re: AP2000
I'm not surprised. Your ISA theory sounds pretty realistic, and it's good for me, since it means that I don't to find some crazy hookup in order to connect the audio card. I'll take those pictures for you tonight - I guess I'll just take them with a real camera instead of with my phone (although my phone does take pretty decent picturestin wrote:Nice
Can I ask a favour? Can you take a single high resolution photo of each side of the 3 cards and post them on your flickr? I am trying to reverse engineer any kind of bus communication.
<edit> From what I can see, ISA bus pins 6, 8 and 15 are connected to each other between the cards (the other pins are voltages and ground). They are even labelled 6 8 and 15 on the audio card. According to what I know there's no reason for this other than inter-ISAcard communication....
)EDIT: Here are high-resolution versions of the pictures I took with my phone last night if it helps, I'll get you better ones tonight: cards/
Re: AP2000
Yeah I did see the pics are pretty good from the phone. Might have persuaded me to upgrade to iphone4. I presume iphone5 is going to be a few months....
Re: AP2000
Yeah, probably June. I'll probably be getting it, since AT&T is going crazy with my upgrades and gives me a discounted phone every year (I've had every model of iPhone so far :p)tin wrote:Yeah I did see the pics are pretty good from the phone. Might have persuaded me to upgrade to iphone4. I presume iphone5 is going to be a few months....
Back on topic, it seems that we've cracked this code of how the audio card knows when to switch audio. The Amiga sends 0x01, 0x02, or 0x03 out through its TX port (http://www.ariweinstein.com/prevue/view ... p=559#p559, http://www.ariweinstein.com/prevue/view ... p=787#p787) and then the data demodulator card forwards it through the ISA bus to the audio demod/switcher card.
Re: AP2000
OK so I think I have figured at least something.
What I suspect is the RX pin of the serial port is pushed through a nand gate, a serial UART and a BCD/binary to decimal/octal translator (it doens't matter which actually as we only use the first 3 states). I *THINK* (based on very little knowledge - I am brand new to this kind of reverse engineering) that means that the raw serial code sets some lines based on the binary version of the code then the BCD/decimal converter turns just ONE line on based on the value that came through.
As far as I can work out then 0x01 sets pin 6 of the ISA bus, 0x02 sets pin 8 and 0x03 sets pin 15. After I wrote this I remembered something like this has been said before, searched and found it ties in exactly with what you said before (even though I never saw the Amiga send back 0x01 etc). <edit> Your links above point to this.
*SO* the audio switching *IS* done over the ISA bus but in a bit more of a mechanical way than I thought, it just sets one of the 3 ISA pins high, which indicates the feed the audio demod switches to.
<edit> LOL I see you edited while I was typing - edited accordingly.
What I suspect is the RX pin of the serial port is pushed through a nand gate, a serial UART and a BCD/binary to decimal/octal translator (it doens't matter which actually as we only use the first 3 states). I *THINK* (based on very little knowledge - I am brand new to this kind of reverse engineering) that means that the raw serial code sets some lines based on the binary version of the code then the BCD/decimal converter turns just ONE line on based on the value that came through.
As far as I can work out then 0x01 sets pin 6 of the ISA bus, 0x02 sets pin 8 and 0x03 sets pin 15. After I wrote this I remembered something like this has been said before, searched and found it ties in exactly with what you said before (even though I never saw the Amiga send back 0x01 etc). <edit> Your links above point to this.
*SO* the audio switching *IS* done over the ISA bus but in a bit more of a mechanical way than I thought, it just sets one of the 3 ISA pins high, which indicates the feed the audio demod switches to.
<edit> LOL I see you edited while I was typing - edited accordingly.