Enterprise Forever
:UK => Hardware => Display => Topic started by: Zozosoft on 2008.January.21. 21:45:13
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Enterprise pinouts (http://ep.homeserver.hu/Dokumentacio/Konyvek/EXOS_2.1_technikal_information/hardware/pinout.html)
SCART pinout (http://en.wikipedia.org/wiki/SCART)
Connected wires: RED, GREEN, BLUE, CSYNC and AUDIO Left and Right, Mode Switch, and signal Grounds.
Because the Enterprise not produce standard signal levels, not all monitors can display correctly the EP picture.
For correcting this, needed to put some resistors to signal wires:
(http://www.ep128.hu/Ep_Konyv/Pic/EnterFace14.gif)
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Is it possible to make an S-Video or Composite cable as well?
If so, where can I order it, I'm not good with soldering stuff :)
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The Enterprise have only monochrome composite video signal in the monitor connector.
For use a color composite video signal, needed some modifications inside the machine.
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crap, looks like I have to ask a friend to modify it then. Does the above also show the modification in the EP?
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I have monitor with RGB input (Samsung SynkMaster 700p+) with BNC connectors (R) (G) (B) (H/V) (V)
It's possible to connect it to EP?
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Probably it's not possible. I have a few modern VGA monitors with those connectors, but none of them can work with those low frequencies what EP has. It is still possible that your monitor is an exception, but only a very few monitor can work on those frequencies.
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That's BAD :(...
but how can I test that?
what pins must be connected (except RGB)
EP
HSYNC
VSYNC
CSYNC
Monitor
H/V
V
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I don't know exactly the electronic standards whose signals are the signals named r,g,b, v, h/v, hsync, vsync, csync. As far as I know, you cannot exactly know what is on one connector when it is named for example csync. There are different composite syncron signals in the electronic industry. You have to know the special device to know what is on its connector named csync. So I usually make some try. These signals are very low level ones, nothing will happen when you connect the wrong connectors. You will not have picture, or good picture only, at a wrong connector combination.
So we are sure in 4 connectors:
r (monitor) - r (EP)
g (monitor) - g (EP)
b (monitor) - b (EP)
v (monitor) - vsync (EP)
you have to try only two combinations:
h/v (monitor) - hsync (EP)
or
h/v (monitor) - csync (EP)
One monitor will understand, and work with both hsync and csync, one will understand only one of them.
Maybe your monitor will not switch to the BNC input automatically, in this situation you have to switch it manually from the monitor's menu.
But 99% after the connection you will see a black screen, or a text something like this:
Out of frequency
If you will have a good picture, I will buy a monitor like your one ! :)
Good luck!
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Thanks!
I'll try it next week (or two...)
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This is the result:
CRT TV:
[attach=1]
[attach=2]
LG M208WA LCD
[attach=3]
[attach=4]
Tried to omit the resistors but it didn't work - the LCD showed only a hint of the text on white screen, the TV showed just a white screen.
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This is the result:
Great!
Tried to omit the resistors but it didn't work - the LCD showed only a hint of the text on white screen, the TV showed just a white screen.
Yes, only few displays works without the resistors, for example Philips CM833x
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Is it possible buy monitor cable somewere? :oops:
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Prompt the correct connection:
[attachimg=1]
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Prompt the correct connection:
It is a GND (A2 or B2).
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Hello.
Prompt where I must connect Mode Switch and CSYNC
[attachimg=1]
Simply, I'm afraid do something wrong. :oops:
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Nice graphics! Which program used for drawing?
Prompt where I must connect Mode Switch and CSYNC
Switch from EP B6 to SCART pin 8 (and with the 470 Ohms to pin 16)
CSYNC from EP B5 to SCART pin 20, usually these also require a 100 Ohm resistor.
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Thanks for help! :)
Which program used for drawing?
Photoshop only (drawing process relaxes me).
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Photoshop only (drawing process relaxes me).
When it is finished with the last two wires then possible use your graphics on Enterprise webpages?
And do you want some more relaxing? :) If yes then can you make same nice graphics for other cables? (Printer, Serial, Joystick, ...)
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No problem. :)
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No problem. :)
Thanks!
I will write the connection pinouts?
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it would be nice
B2 - 4 is correct?
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B2 - 4 is correct?
Yes, both B2 and A2 are GND, it is on the Scart: 4, 5, 9, 13, 18, 21
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it would be nice
Ok, I writed some to here. (http://enterpriseforever.com/hardware/other_cable_connections-t705.0.html;msg27755#msg27755)
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just built a cable. works ok on my EP64 with abit of sound interference (ground issues)
on my EP128 its is very bright colours with bleed/shimmer around edges.
are there different scart outputs for different boards? im thinking maybe higher resistors on the RGB 330/470?
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are there different scart outputs for different boards? im thinking maybe higher resistors on the RGB 330/470?
Few days ago Bruce also recommended higher resistors. (http://enterpriseforever.com/hardware/resistor-values-for-scart-cable/)
(http://enterpriseforever.com/hardware/resistor-values-for-scart-cable/)
The 100 ohms come from Hungarian magazine (1989).
Theoretically all motherboards same, but I does not rule out undocumented changes during the production.
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Theoretically all motherboards same, but I does not rule out undocumented changes during the production.
Not to mention the effects of 30 years on component values!
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Hi bruce im in agreement.
I picked up a 64 and a 128 last week.
Made a cable up with 100R and is perfect on the 74 but major bleed of colours on the 128
Im thinking possible differnces on the issue of boards etc?
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Im thinking possible differnces on the issue of boards etc?
It's possible but I don't think we're aware of any production differences - but zozo is the expert on that sort of thing! Internally there are only a few resistors between digital TTL logic and analogue RGB output - more likely one or more of those have become low in value over the years!
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This schematic contain (http://enterprise.iko.hu/schematics/EP64-3~1.jpg) the colour DAC resistors.
I will check some different version motherboards, about all using same values?
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I have built a new cable with 330r on rgb.
Darker colours but still fuzzy edges/bleed.
Any ideas where to look? What to change?