It is currently Sun May 27, 2018 5:43 pm

All times are UTC + 1 hour [ DST ]




Post new topic Reply to topic  [ 13 posts ] 
Author Message
 Post subject: IEC cables
PostPosted: Sat Mar 08, 2008 12:50 pm 
Offline

Joined: Thu Dec 27, 2007 7:05 pm
Posts: 30
Location: The Netherlands
Hello! I have done some testing with different IEC cables, and it turns out that cables without proper shielding do NOT work well for use between a commodore and a disk-drive, like the 1541. :!:

There are some so called 'high quality' video cables on the market with the IEC-alike 6-pin DIN connectors on both ends, but they have the shield of the cable connected to pin 3, with is ATN in the IEC definition. Due to excessive crosstalk, it will cause serious problems. :shock:

So guys, tell me.. where do you get your extra IEC cables? :?:


Top
 Profile  
Reply with quote  
 Post subject:
PostPosted: Sat Mar 08, 2008 2:45 pm 
Offline

Joined: Mon Dec 31, 2007 2:08 pm
Posts: 3
I make them myself.

I have used those video cables too, never a problem even with disk turbos.. I'm sure I have a couple of them mixed up with the rest in my box 'o cables.


Top
 Profile  
Reply with quote  
 Post subject:
PostPosted: Sat Mar 08, 2008 3:27 pm 
Offline
User avatar

Joined: Sun Jun 03, 2007 6:43 am
Posts: 130
Location: Rethan Manor, Balmora, Hlaalu District
This is an interesting coincidence that you should talk about this right now, coz just today I tested a serial cable I bought from Protovision and it didn't seem to work properly. In the C128 monitor I get I/O Errors #5 and then the directory was garbled up until it worked the next time.

Also, I bought a monitor cable, but it gives a monochrome picture on my television. Why would that happen? Should I sent these cables back?

_________________
Commodore 128 Programmer
City of Kouvola, Finland

http://mydarkgothvampiricplace.endofthe ... Commodore/


Top
 Profile  
Reply with quote  
 Post subject: IEC cable drama
PostPosted: Sat Mar 08, 2008 3:39 pm 
Offline

Joined: Thu Dec 27, 2007 7:05 pm
Posts: 30
Location: The Netherlands
FMan wrote:
This is really funny that you should talk about this right now, coz just today I tested a serial cable I bought from Protovision and it didn't seem to work properly. In the C128 monitor I get I/O Errors #5 and then the directory was gargbled up until it worked. Should I sent these cables back?


Whether you send the cables back is, of course, your own choice. You could check with a multimeter whether outer rings of the plugs on both ends are electrically connected. In that case, it is very likely that that is used for shield in the cable. If not, some other pin is used as shield; in my case it was pin 3, ATN. Pulling ATN low caused other pins to have a large dip, too. This causes fast demo loaders to fail. I could imagine that C128 burst-mode also fails.

What do you mean by "until it worked"? You still got the cable to work reliably?

What I am concerned about is whether I should deliver these cables with the 1541 Ultimate Plus. I never officially indicated that it comes with a cable, though. I am worried that if I do supply the cable, that people would blame the 1541U for not working properly, while in fact it is just a poor cable. The question is, should *I* send my cables back? (I have *many* :? ).


Top
 Profile  
Reply with quote  
 Post subject:
PostPosted: Sat Mar 08, 2008 4:02 pm 
Offline
User avatar

Joined: Thu Jan 12, 2006 1:52 am
Posts: 203
Location: Denmark
Hmm.. this is interresting.. I usually get my cables from my infinite storage of vintage crap.. only problem is that I sometimes forget where I place stuff ;-) ..anyways, I remember at one point I couldn't locate a cable for a 1541 and ended up just hacking some shit together with regular door-bell quality wires and some paper clips for "plugs". As far as I remember it worked. Problem is that I cant remember if it worked with fastloaders and such. I somehow get the urge to try this out again ;-)

If "I" were to decide to ship cables, I would either build them myself or get a contractor you can physically kick in the balls for a bad job to do it for me.


Top
 Profile  
Reply with quote  
 Post subject: Re: IEC cable drama
PostPosted: Sat Mar 08, 2008 4:30 pm 
Offline
User avatar

Joined: Sun Jun 03, 2007 6:43 am
Posts: 130
Location: Rethan Manor, Balmora, Hlaalu District
gideonz wrote:
I could imagine that C128 burst-mode also fails.

Yes, that was my thought too, but I tested it with 1541. I wasn't able to load GP Circuit that uses n0sd0s. But if I'm having a hard time just loading the directory, there is something badly wrong. :?

gideonz wrote:
What do you mean by "until it worked"? You still got the cable to work reliably?

Until I managed to load the disk directory correctly... I'm not ready to call these cables crap yet, coz my understanding is that they are built by a person who knows what he is doing, but I am a bit worried.

I actually ordered a variety of cables, around ten in total, so I will try the other two IEC cables that I got, to see if it's just this one cable that is wonky. But I shall email Förster about the problem.

It would be cool to supply a cable with your cart, so I hope you will work to find a realiable solution and wish you luck with it! :D

_________________
Commodore 128 Programmer
City of Kouvola, Finland

http://mydarkgothvampiricplace.endofthe ... Commodore/


Top
 Profile  
Reply with quote  
 Post subject:
PostPosted: Sat Mar 08, 2008 11:00 pm 
Offline

Joined: Thu Dec 27, 2007 7:05 pm
Posts: 30
Location: The Netherlands
Devia wrote:
Hmm.. this is interresting.. [...] ..anyways, I remember at one point I couldn't locate a cable for a 1541 and ended up just hacking some shit together with regular door-bell quality wires and some paper clips for "plugs". As far as I remember it worked.


Actually, loose wires will work considerably better than tightly coupled wires with a shield that is not used correctly (i.e. not as return path but for data).

The field energy that causes adjacent wires to react to each other is far larger when wires are packed together than for separate wires. This mutual influence is called 'crosstalk'. So your paperclip solution isn't as bad as you think! (Although it probably emits more electric and magnetic waves and is more susceptible to picking up any.)

The function of a shield in cables like these is twofold: shielding (obviously), and providing a low-impedance return path for the data signals. In a good cable and connector pinout design, shield is just shield, and each signal has its own return path. But let's not forget we're talking 80's here. :wink:


Top
 Profile  
Reply with quote  
 Post subject: Re: IEC cable drama
PostPosted: Sun Mar 09, 2008 2:46 am 
Offline

Joined: Tue Feb 07, 2006 4:55 am
Posts: 23
Location: Seattle, USA
gideonz wrote:
Whether you send the cables back is, of course, your own choice. You could check with a multimeter whether outer rings of the plugs on both ends are electrically connected. In that case, it is very likely that that is used for shield in the cable. If not, some other pin is used as shield; in my case it was pin 3, ATN. Pulling ATN low caused other pins to have a large dip, too. This causes fast demo loaders to fail. I could imagine that C128 burst-mode also fails.

<snip>

What I am concerned about is whether I should deliver these cables with the 1541 Ultimate Plus. I never officially indicated that it comes with a cable, though. I am worried that if I do supply the cable, that people would blame the 1541U for not working properly, while in fact it is just a poor cable. The question is, should *I* send my cables back? (I have *many* :? ).


Should you deliver cables that don't work with fastloaders?
Of course not! Dig a hole in your back yard and bury them. :shock:


Top
 Profile  
Reply with quote  
 Post subject:
PostPosted: Sun Mar 09, 2008 9:56 am 
Offline

Joined: Thu Jan 10, 2008 9:53 am
Posts: 10
Location: Sweden
jsaily (on Lemon64) makes these cables. They seem to work. I don't know how the shield is connected, and I haven't tried fastloaders with mine.

Image


Top
 Profile  
Reply with quote  
 Post subject: Re: IEC cable drama
PostPosted: Mon Mar 10, 2008 2:22 pm 
Offline

Joined: Thu Dec 27, 2007 7:05 pm
Posts: 30
Location: The Netherlands
TheBeck wrote:
gideonz wrote:
<snip>
What I am concerned about is whether I should deliver these cables with the 1541 Ultimate Plus. I never officially indicated that it comes with a cable, though. I am worried that if I do supply the cable, that people would blame the 1541U for not working properly, while in fact it is just a poor cable. The question is, should *I* send my cables back? (I have *many* :? ).


Should you deliver cables that don't work with fastloaders?
Of course not! Dig a hole in your back yard and bury them. :shock:

I totally agree!


Top
 Profile  
Reply with quote  
 Post subject:
PostPosted: Tue Mar 11, 2008 2:37 pm 
Offline
User avatar

Joined: Sun Jun 03, 2007 6:43 am
Posts: 130
Location: Rethan Manor, Balmora, Hlaalu District
gideonz wrote:
But let's not forget we're talking 80's here. :wink:

Well, I'm pretty sure there was distinction of shield and signal ground back then - maybe just not for Tramiel... :D Anyways, I remember using a twin cable for synchronous serial transfer - separate DATA and CLK with their own ground, but I still couldn't get more than 8K per second with a ten-meter cable.

But as memory serves, the cables used the shield for return path. :lol: BTW, I tested the two other cables I got from Protovision and they appear to work, so it's just the one IEC cable that is fuxxored, as I suspected - and hoped. Dunno what I'll do with it. Doesn't make much sense to send it back.

http://www.fooman.fi/temp/serielles-ver ... kaputt.jpg

_________________
Commodore 128 Programmer
City of Kouvola, Finland

http://mydarkgothvampiricplace.endofthe ... Commodore/


Top
 Profile  
Reply with quote  
 Post subject:
PostPosted: Tue Mar 11, 2008 10:02 pm 
Offline
User avatar

Joined: Wed Sep 05, 2007 3:03 pm
Posts: 44
Quote:
Doesn't make much sense to send it back


It would be great to get it back in that "Paras Kebab" paper though :D :D


Top
 Profile  
Reply with quote  
 Post subject:
PostPosted: Sun Mar 16, 2008 3:32 am 
Offline
User avatar

Joined: Sun Jun 03, 2007 6:43 am
Posts: 130
Location: Rethan Manor, Balmora, Hlaalu District
Hahah. I knew somebody would comment on it, but it just happened to be underneath. :) I have now emailed Oliver Förster three (3) times without an answer - I hope this doesn't mean he won't care about the customer once he's out the door with his stuff...

_________________
Commodore 128 Programmer
City of Kouvola, Finland

http://mydarkgothvampiricplace.endofthe ... Commodore/


Top
 Profile  
Reply with quote  
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 13 posts ] 

All times are UTC + 1 hour [ DST ]


Who is online

Users browsing this forum: No registered users and 2 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
cron
Powered by phpBB® Forum Software © phpBB Group