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donmck

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Joined: 09/06/2011
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Posted: 06:40am 22 Aug 2011

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Went and paid a visit to the thread I started on the piclist about the Maximite, and noticed this question posed:

[code]
by David Bley Aug 21, 2011;
I don't know much about video displays. Has anyone got a code/hardware mod for
Maximite to support composite video for NTSC? Just curious.

I think that Maximite is cool. Does anyone remember how much of a productivity boost
it was to go from a typewriter to a word processor?
[/code]

I know I have it as Wish List 25, but I am wondering if any of our US Maxiteers have marched forward with this one yet.

Cheers Don...

https://www.dontronics.com

Gizmo

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Posted: 06:49am 22 Aug 2011

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I'm probably wrong but isn't the differences between PAL and NTSC, apart from the native TV resolution for the country, just the way the colour information is processed? With its B&W image the Maximite should be OK on a PAL or NTSC screen.

Glenn

The best time to plant a tree was twenty years ago, the second best time is right now.
JAQ

sparkey

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Joined: 15/06/2011
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Posted: 07:00am 22 Aug 2011

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hey don is that program that you just got hold of for the lcd sheild on your site under the ftp stuff...regards..

technicians do it with least resistance

donmck

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Posted: 07:24am 22 Aug 2011

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sparkey said hey don is that program that you just got hold of for the lcd sheild on your site under the ftp stuff...regards..

I guess you mean this one:

Data and Schematics and all other relevant files are available from:
http://www.themaximitecomputer.com/max/Programs/
Then Select Hardware, then Dontronics, then LCD

You will find the details there to be able to convert this LCD to operate on 3.3V A/D for the press button switches, so that it can be used on a Maximite Computer System. This conversion and code, was done by my good friend Mick Gulovsen.

Cheers Don...

https://www.dontronics.com

haiqu

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Joined: 30/07/2011
Location: Australia
Posts: 152

Posted: 01:17pm 22 Aug 2011

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Gizmo said I'm probably wrong but isn't the differences between PAL and NTSC, apart from the native TV resolution for the country, just the way the colour information is processed? With its B&W image the Maximite should be OK on a PAL or NTSC screen.

Glenn

Quite a few differences. Frame rates, number of lines per frame, etc.

Expect to get requests for SECAM too, there is one of these on order in Russia and the French use it as well.

Shouldn't be much of a change anyhow, and I suspect most people will use an old VGA monitor.

Rob

unzip, strip, touch, finger, grep, mount, fsck, more, yes, fsck, fsck, fsck, umount, sleep

sparkey

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Posted: 01:32pm 22 Aug 2011

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i argree ssurely peop`s will be better off using a old monitor rather than tie up their tv sets even though they could run the rca video/pal to most or their sets any way ...regards ...even wiriring a s-video lead to fit teir sets would not be difficult ,,Edited by sparkey 2011-08-23

technicians do it with least resistance

sparkey

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Posted: 01:38pm 22 Aug 2011

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it would be simpler if sombody just made an adaptor plug on a board coverting the vga too s-video....sparkey ..i am loking at this one my self dont think it will be much of a challenge...///

technicians do it with least resistance

sparkey

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Posted: 01:51pm 22 Aug 2011

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just looking at "wes components " in asfeild n.s.w." they have hundreds of different adaptors including pal to s-video "02_97979866"

technicians do it with least resistance

donmck

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Posted: 08:05pm 22 Aug 2011

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Some one in this Forum posted a story with picture on just this. He had a VGA to video adapter, I think to basically save diving inside the box, and wiring to the header.

So, I wonder about the discrete differences, as mentioned earlier in this thread. Video isn't my thing.

Cheers Don...Edited by donmck 2011-08-24

https://www.dontronics.com

sparkey

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Posted: 08:13pm 22 Aug 2011

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YES THAT MAY HAVE BEEN ME DON I HAVE A VGA COVERTER IT HAS THREE INPUTS
:VGA FROM MONITOR
:S=VIDEO
:PAL RCA

:OUTPUTS TO A VGA MONITOR HAS A REMOTE CONTROL ...

and i think that the video game shops sell a converter unit i do rember buying one for a customer who needed to attach her artari to her tele vision...regards Edited by sparkey 2011-08-24

technicians do it with least resistance

aargee
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Joined: 21/08/2008
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Posts: 255

Posted: 09:45pm 22 Aug 2011

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I made that little dongle (see here) that hangs off the VGA port and is wired to an RCA connector. If you look at the circuit, the composite video signal appears as part of the VGA signal on the connector.

- Rob.

For crying out loud, all I wanted to do was flash this blasted LED.

donmck

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Posted: 10:05pm 22 Aug 2011

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Oh, of course, silly Donnie.

Thanks Rob.

Perhaps a Basic command to toggle.

So we need look up tables of some sort, for NTSC and SECAM operation.

I know most people don't use it, in fact I think Rob is the only one to date that has indicated he has, but obviously it is a concern for many.

Cheers Don...Edited by donmck 2011-08-24

https://www.dontronics.com

donmck

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Posted: 12:24am 21 Oct 2011

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This NTSC thing keeps popping up, and I am wondering if we can revisit it, and get the problem solved for all non-Australian users.

Would it be possible to poke the NTSC values into the correct memory locations, so it can be tested by a reasonable number of potential users?

I am open to any suggestions.

Cheers Don...

https://www.dontronics.com

ksdesigns

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Joined: 25/06/2011
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Posts: 143

Posted: 12:49am 21 Oct 2011

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I made a version for some one on here for NTSC didn't hear back if it worked for him ok
worked on my monitor fine but you only get 16 lines instead of 18
we have less scan lines

Here's the HEX if anyone wants to test it
ken

CircuitGizmos

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Posted: 12:49am 21 Oct 2011

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I have had far from ideal results using the numbers I was given and recompiling the firmware.

Micromites and Maximites! - Beginning Maximite

CircuitGizmos

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Posted: 12:53am 21 Oct 2011

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ksdesigns said I made a version for some one on here for NTSC didn't hear back if it worked for him ok
worked on my monitor fine but you only get 16 lines instead of 18
we have less scan lines

Here's the HEX if anyone wants to test it
ken

Your hex file does the very same thing as the image I just posted.

Micromites and Maximites! - Beginning Maximite

CircuitGizmos

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Posted: 12:59am 21 Oct 2011

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I do have a new tv/monitor that will lock on to this version of NTSC, but then it will lock on to PAL, too.

Micromites and Maximites! - Beginning Maximite

ksdesigns

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Joined: 25/06/2011
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Posted: 01:04am 21 Oct 2011

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does this monitor have any adjustments ? vert/horz ?
would like to know how much you have to tweek it to lock
ken

CircuitGizmos said I have had far from ideal results using the numbers I was given and recompiling the firmware.

CircuitGizmos

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Posted: 01:13am 21 Oct 2011

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The pictured monitor has vertical hold, no horizontal hold adjustment.

Monitor #2 will display an ntsc signal from another source, but displays MM video (still scrambled) for a second before giving up.

My modulator input (ntsc input into all of the connected house tvs) shows nothing.

Direct into a modern LCD TV works. (So does PAL)

I wonder if the signal voltage is too low, or the sync signals (blacker-than-black) are too high. Edited by CircuitGizmos 2011-10-22

Micromites and Maximites! - Beginning Maximite

donmck

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Posted: 01:14am 21 Oct 2011

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Tsvetan at Olimex couldn't lock onto an NTSC file either with his TV.

Was that the same build Ken?

Cheers Don...

https://www.dontronics.com

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