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Question: Which peripheral would you most like for the Videopac7000/Odyssey2?
Trackball
Mouse
Printer
High score save device
Pause game device

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Sweersa
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« Reply #15 on: September 30, 2008, 01:02:20 PM »

Would it be possible to connect the detachable joystick with the DB-9 looking serial port into a computer with that same port?  It fits...but I wonder how one could get it to act like a mouse...with the action button as the click.

No way! The computer expects a serial data stream, all the O2 joystick has to offer is 5 on/off buttons, which are connected directly to the port.


lol Well scratch my idea.  I can always dream though...
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manopac
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« Reply #16 on: October 01, 2008, 12:30:57 AM »

I don't know anything about the hardware inside the existing trackball for the Odyssey2, but since it works with existing games and it is connected to the regular joystick port, the only thing it could do is for example: as long as you roll the ball to the left, it makes the line for LEFT on the joystick port active (low), which would be the same as keeping the joystick pressed to the left. The same for RIGHT, UP and DOWN. When moving the ball diagonally, it should make two lines active at the same time.

thats what I thought :-( still I can't believe the "original" trackball found is just a device like that ... who's the lucky one who got it ? can that person maybe take a few pictures of the insides ? (or do those exist already and I just don't know about it ...)
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Rene_G7400
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« Reply #17 on: October 01, 2008, 01:27:21 AM »

thats what I thought :-( still I can't believe the "original" trackball found is just a device like that ...

Why not? What would you expect it to do?

I would like to see the inside of the trackball too.

You can find a "lucky one" here:http://www.thelogbook.com/phosphor/odyssey2/trackball/
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manopac
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« Reply #18 on: October 01, 2008, 01:29:34 AM »

thats what I thought :-( still I can't believe the "original" trackball found is just a device like that ...
Why not? What would you expect it to do?

somehow I was hoping it would send shorter or longer pulses of left / right etc. depending on the speed you move the ball with Smiley
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« Reply #19 on: October 01, 2008, 08:27:43 AM »

Hmm, if the trackball just "emulates" a joystick, I wouldn't see the sense of a trackball ...

Edit: Look at that photo: http://www.thelogbook.com/phosphor/odyssey2/trackball-back/

On the back of the box it says "Phenolic ball offers the magic of 360 degree movement to an infinite number of positions, and controls the speed of on-screen objects, as well". Maybe PDF could tell us if the trackball really speeds up objects when you move it faster? Because beside the exact movement this is the second main reason for a trackball for me.
« Last Edit: October 01, 2008, 09:09:02 AM by ccc--- » Logged

Gorf
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« Reply #20 on: December 20, 2008, 11:26:39 PM »

Here?s seems to be an explanation how to insert pause in a VCS, I don?t know if can be applied to Ody.
(seems I forgot the link):
http://picasaweb.google.com/british1500/VideogamingIllustratedOctober83#5072572165183084114

No, apparently some Atari 2600 games already had a pause function programmed in, the only "problem" was that you had to use the switches on the console. The only thing this mod does is build the switches into the controller, so it's easier to reach them.

Even if a pause function on the Odyssey2 would be possible, it would require hardware modifications inside the console. Some kind of plug-in unit for the cartridge-port or joystick-port would not be possible.



Yeah, its a shame Magnavox did not think of putting an expander connector
on the O2's.

As far as what I'd like to see?

I would like to see a cart design with a lot of ROM and 4k RAM on it.

Or if only that expnader exsisted, it would have been nice to add
additional Video other than the character generator. I think it is
possible to add another VDCin a 8048 circuit. I thought I remembered
reading that in the data sheet somewhere.
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Rene_G7400
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« Reply #21 on: December 21, 2008, 03:04:15 AM »

Yeah, its a shame Magnavox did not think of putting an expander connector
on the O2's.

They did think of it later, the Odyssey3 has one.
The cartridge port of the O2 already has more options than the 2600.

I would like to see a cart design with a lot of ROM and 4k RAM on it.

That's not impossible now.

Or if only that expander existed, it would have been nice to add
additional Video other than the character generator. I think it is
possible to add another VDC in a 8048 circuit. I thought I remembered
reading that in the data sheet somewhere.

Yes, that possible, but if you want more video options, you should use the G7400...
« Last Edit: December 21, 2008, 03:07:14 AM by Rene_G7400 » Logged
Gorf
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« Reply #22 on: December 21, 2008, 03:56:32 AM »

They did think of it later, the Odyssey3 has one.
The cartridge port of the O2 already has more options than the 2600.

That's not saying much as the 2600 had much to be desired. Tongue  But yes the O2 does allow
a much better expansion.


"......lot of ROM and 4k RAM on it."

That's not impossible now.

I know and hope to realize it someday. Smiley


Yes, that possible, but if you want more video options, you should use the G7400...

Does that video chip allow RAM buffered high res? Can you 'fake' a screen mapping
characters in RAM like the VIC 20 does?...I looked at the spec sheet and it says it
can look at ram maps.... I am wondering if this is the case with the G7400 chip.

The only thing about using the G7400 is thre are only a handful of users that would
ever get to use a cart on a real G7400. I wish I had one but dont so I'd have to rely
on my emu myself. Cheesy

I make games because I want to release carts because there aint nothing like the
real thing. A nice new box and label. With a fresh VP/o2 game inside. Smelling all
brand new and all.

 Cool
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grgh
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« Reply #23 on: December 21, 2008, 07:50:57 AM »

A nice new box and label. With a fresh VP/o2 game inside. Smelling all
brand new and all.

Ah well kinda, except its never been very cost effective to produce new parts so new releases have always been done on old smelly carts  Grin
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Rene_G7400
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« Reply #24 on: December 21, 2008, 01:57:59 PM »

Does that video chip allow RAM buffered high res? Can you 'fake' a screen mapping
characters in RAM like the VIC 20 does?...I looked at the spec sheet and it says it
can look at ram maps.... I am wondering if this is the case with the G7400 chip.

I'm not sure I completely understand what you mean.
Basically the "Plus" graphics chip (EF9340/9341) displays 40x24 ASCII characters. The ASCII codes for each position are stored in 1k RAM. There's a special GRAPHICS mode, instead of the regular characters, blocks of 2x3 small rectangles are displayed. ASCII codes 80-FF are for special purposes, codes A0-FF for self defined characters, both in text and in graphics mode, so you can define 192 characters (8x10 pixels). Those are stored in 2k RAM, but this RAM is not directly accessible by the 8048, only through the EF9341. The same is true for the 1k page RAM, which is actually 1k x 16 bit, because you can specify the color and some other things for each character.
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Gorf
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« Reply #25 on: December 21, 2008, 10:48:13 PM »

A nice new box and label. With a fresh VP/o2 game inside. Smelling all
brand new and all.

Ah well kinda, except its never been very cost effective to produce new parts so new releases have always been done on old smelly carts  Grin


Well....I'll sanitize them first.... Tongue

Since you replied.....I ask you this.......where do we go for sources of shells
and PC boards?



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Gorf
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« Reply #26 on: December 21, 2008, 10:58:44 PM »

Does that video chip allow RAM buffered high res? Can you 'fake' a screen mapping
characters in RAM like the VIC 20 does?...I looked at the spec sheet and it says it
can look at ram maps.... I am wondering if this is the case with the G7400 chip.

I'm not sure I completely understand what you mean.
Basically the "Plus" graphics chip (EF9340/9341) displays 40x24 ASCII characters. The ASCII codes for each position are stored in 1k RAM. There's a special GRAPHICS mode, instead of the regular characters, blocks of 2x3 small rectangles are displayed. ASCII codes 80-FF are for special purposes, codes A0-FF for self defined characters, both in text and in graphics mode, so you can define 192 characters (8x10 pixels). Those are stored in 2k RAM, but this RAM is not directly accessible by the 8048, only through the EF9341. The same is true for the 1k page RAM, which is actually 1k x 16 bit, because you can specify the color and some other things for each character.


Well in the vic -20 you only had a text screen. However, you could point the
character data to anywhere in the VIC-20 memory space. So now your char
ROM is actually in RAM.

to achive a psuedo hi-rez screen you lay ou characters in the following manner

if you wanted a small 64 x 64 pixel buffer....

A I   Q Y  6 @ ) >
B J   R  Z 7 #  [ ?
C K  S  0 8  $  ] :
D L  T  1 9  % ` '
E M  U 2  -  ^ ~ "
F N  V 3  =  & ,  {
G O W 4  + *  .  }
H P  X 5  !  (  < |

These are not in the correct ASCII order as Im going of the top of my head
but just so you get the idea.

This would be for one color pixels.
Cut the Horz rez in half in multi color mode

How if you can indeed point the Character ROM pointer
to ram on the VP+ chip, then you culd do something similar.

I would imagine the 8048 would have to tell the VP+ chip what to do.

The VIC-20 vid chip had full access to the entire bus. It was more than
possible to pull off double and triple buffers using this.



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Rene_G7400
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« Reply #27 on: December 22, 2008, 12:58:46 AM »

Sounds like it doesn't work the same for the G7400. The Plus-graphics chips have their own private RAM and internal ROM. As said you can define 192 character patterns of 8 by 10 pixels yourself. A limitation is that a character only has a foreground and background color, so inside the 8x10 pixels areas you can only have two different colors.
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Rene_G7400
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« Reply #28 on: December 22, 2008, 01:00:01 AM »

Since you replied.....I ask you this.......where do we go for sources of shells
and PC boards?

eBay, or collectors with lots of spare carts...
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Gorf
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« Reply #29 on: December 22, 2008, 05:33:14 AM »

Sounds like it doesn't work the same for the G7400. The Plus-graphics chips have their own private RAM and internal ROM. As said you can define 192 character patterns of 8 by 10 pixels yourself. A limitation is that a character only has a foreground and background color, so inside the 8x10 pixels areas you can only have two different colors.


I know cost is usually the underlying reason for not going beyond however,
Its a shame Philips did not look ahead on the choice of added graphics for the
G7400. I think a new VDC with double the current resolution and instead of
adding more sprites just allow the VDC to point to a ram based character
set and all 256 characters. This would have allowed for some amazing
custom graphics. Maybe even add a multi color mode where a bit in
the unused byte of the sprites could be allowed to represent one color
or 2bpp color....maybe several modes with even more colors.

In fact, if I had a say at the design table of the O2, I think the only thing
I would have done different was to have a specialized VDC that allowed
for RAM based character sets. This way every game could look completely
unique. It would have required another 512 bytes of ram. Probably not cheap.

However, That means essentially 12 character sized sprites that can look like
anything the developer wanted to. Other than that, the O2 is pretty much
perfect. Bank switching works wonders for address limited processors like the
8048.

Other than the unalterable character set the VDC was perfect. I'd have even
excused the Y position shenanigans for the characters. That means that the
quads would be usable as one big 4x 1 character sprite...perfect for a gorfian
flagship... Smiley You'd beable to set four different characters that you could redefine
the images of. That would be a total of 64 definable sprite images one character
each. You'd essentially then have 4 regular sprites, 12 character sprites and then
for large 4x1 sprites.

Hmmm.....I wonder if I should take a look at the sources to O2EM and see if I can
add that feature just to see how cool it might have been. The problem is, you'd
have to use like pin 15 of port one(currently unused) to support the external ram.
You'd also have to find a signal from the VDC that is also not used and possibly
available for expansion.


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