New G5 and CRT having weird issues...

Try this

Open preferences click on display

Check the monitor installed under color option

Try Generic Monitor or one of the early Apple's

Then click on option select turns the display on and off.

simie said:

Try this

Open preferences click on display

Check the monitor installed under color option

Try Generic Monitor or one of the early Apple's

Then click on option select turns the display on and off.

Click to expand...

I dont know if that will work... its not an ADC display, so I don't know why that setting would exist. Plus I can't find that for my CRT on my Powerbook...

point665 said:

I noticed a weird issue with my new Power Mac G5 (Single 1.8)... I have a 19" Flat Envision CRT hooked up to it, now if the PM is off and I turned on the CRT the PM boots up (just like the Apple Displays did)...

Click to expand...

Yeah, mine did that with a 19" Viewsonic monitor once or twice early on (several months ago), but never since then. Dunno why....

Also if I powerdown or sleep my PM it will wake up/reboot unless I powerdown CRT before doing this.

Click to expand...

Hmm, mine never did that. Not very helpful, I know.

--Eric

If you can't see the options tab then your Mac isn't seeing the crt screen as a digital (which it isn't). So obviously the DVI adapter is wired in a strange way. I wonder if an adapter from a PC digital monitor would correct this or be the same.

It as got to be that the DVI to VGA adapter wiring and the wiring in your monitor plug not being 100% compatible with each other.

Here are the pinouts for the CRT and the DVI plug. When I have rewired these connectors in the past I have never had to connect the ID bit on pins 4 / 11 / 12 / 15.

15pin H/D Connector (http://pinouts.ru/data/VGA15_pinout.shtml)

Pins numbers and signal type
1 red
2 green
3 blue
4 ID bit 2
5 n/c
6 red ground
7 green ground
8 blue ground
9 n/c
10 ground
11 ID bit 0
12 ID bit 1
13 H sync
14 V sync
15 ID bit 3 or SCL

DVI Pin Signal (http://pinouts.ru/data/dvi_pinout.shtml)

Pin numbers and signal type
1 T.M.D.S DATA 2-
2 T.M.D.S DATA 2+
3 T.M.D.S DATA 2/4 SHIELD
4 T.M.D.S DATA 4-
5 T.M.D.S DATA 4+
6 DDC CLOCK
7 DDC DATA
8 ANALOG VERT. SYNC
9 T.M.D.S DATA 1-
10 T.M.D.S DATA 1+
11 T.M.D.S DATA 1/3 SHIELD
12 T.M.D.S DATA 3-
13 T.M.D.S DATA 3+
14 +5V POWER
15 GND
16 HOT PLUG DETECT
17 T.M.D.S DATA 0-
18 T.M.D.S DATA 0+
19 T.M.D.S DATA 0/5 SHIELD
20 T.M.D.S DATA 5-
21 T.M.D.S DATA 5+
22 T.M.D.S CLOCK SHIELD
23 T.M.D.S CLOCK+
24 T.M.D.S CLOCK-
C1 ANALOG RED
C2 ANALOG GREEN
C3 ANALOG BLUE
C4 ANALOG HORZ SYNC
C5 ANALOG GROUND

TMDS (transition minimized differential signaling)

As you can see from both connectors pinout's the wiring is pretty straight forward to make an adaptor cable.

The interesting thing is that the Apple supplies an adaptor thats has a DVI Single link connector on it, which means it should be wired for both analog and digital pins.

The adaptor that Apple should surely haave supplied is a DVI -A which is a High-Res Analog adaptor and only has total of 17 pins in total.

This is why I wondered if they have done something strange inside their adaptor cable hence all your problems.

Information on the DVI specification can be found here
http://www.cs.unc.edu/Research/stc/FAQs/Video/dvi_spec-V1_0.pdf

Here is my thoery what it might be, now someone correct me if I am wrong here.

Take a look page 23 and look at Appendix C

If you look at this page, I think the +5v is the key here. This is connected with the power management in the DVI specification.

If your CRT is using the 5v+ on pin 9 of in 15 HD type connector then this may be the cause of the weirdness as it looks like this acts like a way for the DVI powermanagment to detect the state of the monitor whether its in standby - switched on or switched off.

You could test this by making a patch lead with 15 pin male one end and a 15 pin female socket at the other and not connect pin 9. This would also save you chopping the end off your monitor cable trying to rewire it.

I would just make sure that you get good clean connections on the pins - those plugs are a swine to solder, make sure the solder is fluxed else the wires won't hold.

The connections I would use are

pin 1 Red
pin 2 Green
pin 3 Blue
pin 6 Red Ground
pin 7 Green Ground
pin 8 Blue Ground
pin 10 Sync Ground
pin 13 H-Sync
pin 14 V-Sync

This should be enough to get the picture on the screen. On both the male and female ends you will notice that pins are marked differentlly. Looking from the back of both - pin one is on the left handside whilst on one whilst on the other, pin 1 is on the right.

If you are going to build the cable yourself then I would write the colour in the cable and which pins that you assign them to, this will make life easier.

If the hood is made of metal then most cables the outer screen is used as your earth this can be soldered onto the inside of the metal hood.
Or it is soldered to the outer metal rim of the plug above the pins ( this wire is then inside the hood )

You may be able to purchase a ready made lead that has is already wired up that has a plastic hood that is bolted together, then all you have to do is to remove the hood and check for the +5v pin 9 and desolder the wire.



I would then insulate any desoldered wires from each other, as to avoid any short.

If you get the H-Sync and V-sync wires crossed at one end then you won't get a picture.

Warning

If your cable does not work then disconnect it from your monitor and MAC before making any alterations - heat from your soldering iron can damage your equipment.

Make the changes needed then test the cable again.

I take no responsibility here for your ability to use a soldering iron and for making up cables - their are companies out there that will make cables up for you. Or like I wrote a bit back, get a ready made cable that can be modified. But test the cable first to see if it needs modifying.

I hope that this solves the problem.

I just remembered you can check whether your monitor is using the +5v by simply looking at the pins on the plug - some manufacturers tend to cut out the pin 9.

When looking at the plug you get two pins missing on most CRT screens plugs they are pins 5 and pins 9

If pin 9 is missing then the problem is either directly in the plug on the CRT or like I said with their adaptor.

If I was in the same situation I would first build the patch lead and if that fails to solve the problem then I would cut the plug off the end of the monitor cable and rewire it onto a new plug and test it that way. I don't know if its possible to obtain a DVI Plug and hood, as you could attempt to wire the monitor directly into the new DVI plug, bypassing the Apple adaptor.

Have you tried it yet - and does this cure your problem