English Amiga Board


Go Back   English Amiga Board > Support > support.Hardware

 
 
Thread Tools
Old 22 September 2017, 01:13   #1
Cobe
Registered User

 
Join Date: Jan 2014
Location: Belgrade / Serbia
Age: 34
Posts: 518
CD32 with or without plugged joypad/stick going up constantly

Any ideas?

I have this cd32 for years. We had great times and we still do. But I must confess that in these few years I have connected mega-drive joypad few times and once I hotplugged cd32 joypad. Though it's been a while and nothing happened till now. Also recently my joypad's cable was starting to lose contact so I suspect that it could be the thing that caused this.
It seems that problem is not that persistence and that sometimes it goes away if cd32 is running longer. Though it can also happen that there is no problem on power up but than later it appears.

I could add that year or two ago I replaced those two big main suspect capacitors.

Could it be "just" another capacitor needing time to warm up and refill? Or, I
hesitate to say, its maybe something more sinister, like, akiko going bad...

Re-reading... I should clarify that it acts the same with any regular commodore one button joystick plugged in as with no joystick connected at all.

Last edited by Cobe; 22 September 2017 at 01:18.
Cobe is offline  
AdSense AdSense  
Old 22 September 2017, 01:34   #2
Akira
Registered User

Akira's Avatar
 
Join Date: May 2001
Location: New York
Posts: 18,287
I had this problem in my A500 and it was a multiplexer lying after the joystick port that was faulty. I know nothing about the CD32, but I guess the ports work in about the same manner? Meaning you would have to change it, if you are up to the challenge (must be some surface mount shit).

For the time being I guess you can poke around with a multiplexer following the schematics of the CD32 mainboard http://www.amigawiki.de/doku.php?id=...ice:schematics

A quick look says that U34 is possibly your culprit.
Here's a spec sheet of that multiplexer:
http://www.futurlec.com/74LS/74LS166.shtml
Akira is offline  
Old 22 September 2017, 02:27   #3
Cobe
Registered User

 
Join Date: Jan 2014
Location: Belgrade / Serbia
Age: 34
Posts: 518
Thanks for giving me the next main suspect. I'll investigate when I get time. Though my soldering "skills" are probably poor match for it but I'll have to try eventually.
Cobe is offline  
Old 22 September 2017, 03:21   #4
Akira
Registered User

Akira's Avatar
 
Join Date: May 2001
Location: New York
Posts: 18,287
The resistor pack connected to it might also be the problem. You have to measure it all and see where the problem is. Start with the mux.

I didn't get the problem more or less, it was persistent.

I don't think capacitors can create this issue, but CD32s need full electrolytic capacitor replacements anyway, so you might have to do that anyway. The big ones don't count, it's the tiny ones that are assholes.



Good luck
Akira is offline  
Old 22 September 2017, 19:54   #5
Cobe
Registered User

 
Join Date: Jan 2014
Location: Belgrade / Serbia
Age: 34
Posts: 518
Thanks, I'll need it
Cobe is offline  
Old 23 September 2017, 01:39   #6
xArtx
Registered User
 
Join Date: Jun 2013
Location: Australia
Posts: 637
For the suspect joystick port, connect pin 1 to pin 7,
and if that stops it going up, a resistor pack was bad.
xArtx is offline  
Old 23 September 2017, 15:58   #7
Cobe
Registered User

 
Join Date: Jan 2014
Location: Belgrade / Serbia
Age: 34
Posts: 518
Thanks for the tip.

In last two hours or so I'm mostly sitting in a room with cd32 turned on, no joystick plugged in. On power up there was no problem. In first half an hour no problem. Than in next hour problem appeared shortly few times. I wasn't quick enough to connect pins before problem went away by itself except one time when I'm pretty sure it stopped right at the moment I connected pins. But it didn't reappear the moment I disconnected pins... In past hour problem didn't appear again and I'm waiting for it just to be sure that it wasn't coincidence that it stopped at the same moment.

If its resistor would you know which one would have to be replaced? Those are that surface mount resistors beside the port I guess? Damn they are tiny... With no prior experience would I be able to replace it?
Cobe is offline  
Old 23 September 2017, 16:23   #8
Akira
Registered User

Akira's Avatar
 
Join Date: May 2001
Location: New York
Posts: 18,287
I wouldn't do surface mount components without experience. You need practice.
Akira is offline  
Old 23 September 2017, 16:27   #9
Cobe
Registered User

 
Join Date: Jan 2014
Location: Belgrade / Serbia
Age: 34
Posts: 518
Yeah, you're right. I could find someone to do it for me just need to know which one.

btw, another half an hour passed and now I'm playing it and no problem reappeared.
Cobe is offline  
Old 23 September 2017, 16:31   #10
xArtx
Registered User
 
Join Date: Jun 2013
Location: Australia
Posts: 637
They are usually resistor packs, but in a CD32 maybe individual SMD resistors.
Ideally a rework blower to get them off, but if practiced, with soldering iron.

Ok, while touching the RF shield (perhaps at the edge of joy port 2) to prevent static damage,
stick wire just into joyport 1 pin 1, insert audio CD and load CD player.
When it goes up on it’s own, if touching the other end of the wire makes it go down, resistor pack is bad.
Touch RF shield before touching wire also.
xArtx is offline  
Old 29 September 2017, 02:02   #11
Cobe
Registered User

 
Join Date: Jan 2014
Location: Belgrade / Serbia
Age: 34
Posts: 518
Friend and I played with Amigas yesterday and I can confirm that connecting pin 1 and pin 7 stops it going up. Going up doesn't start again right after I remove wire but after some shorter or sometimes longer period.

Is this enough to confirm that resistor pack is bad?

Are these the one that need to be replaced?
Click image for larger version

Name:	res.jpg
Views:	19
Size:	50.6 KB
ID:	54791
All of them or one? What are their exact number and value which should I know when searching to buy them? Are they fairly cheap and common? If they are I'll replace them all. I mean I'll give it to someone who knows.
Attached Thumbnails
Click image for larger version

Name:	res2.png
Views:	19
Size:	57.4 KB
ID:	54792  
Cobe is offline  
Old 29 September 2017, 16:58   #12
Akira
Registered User

Akira's Avatar
 
Join Date: May 2001
Location: New York
Posts: 18,287
Quote:
Originally Posted by Cobe View Post
Is this enough to confirm that resistor pack is bad?
I don't know, I would test them with a multimeter, and also the multiplexer.
Just to be thorough.
But as I said, without experience with smd and those tiny components, why bother? You could end up doing irreparable damage.

By the way that's not R370 as the schematics say. Can't even find them, it's such a compact motherboard, everything is next to each other.
I can't even find E365 to E368.

[edit] I knew it, the rest are on the underside:

The top side only has bank F

Last edited by Akira; 29 September 2017 at 17:07.
Akira is offline  
Old 29 September 2017, 22:24   #13
xArtx
Registered User
 
Join Date: Jun 2013
Location: Australia
Posts: 637
8 resistors all called R370 yes.
They are all 4.7k, and resistors are common.
xArtx is offline  
Old 03 October 2017, 21:02   #14
Cobe
Registered User

 
Join Date: Jan 2014
Location: Belgrade / Serbia
Age: 34
Posts: 518
Thanks guys. I'm not touching them myself. I'll find someone with experience but hardly he'll have experience with Amigas so I want to know as much as I can to point him out what to check and replace.
Cobe is offline  
Old 03 October 2017, 21:36   #15
solidcore
Registered User

 
Join Date: Sep 2017
Location: birmingham, uk
Posts: 279
Cobe wise decision my friend - I never touched smd before last month but since I've now soldered a tf328 I feel more confident on smd repairs such as the one you're facing . I think the hard part about those little bitters is they're tricky to place tacking a single pad only is the key and moving them into it while you heat the pad up . As for removal I believe putting solder bridge across it helps as you can Heat both sides together - hot tweezers would be nice I should get some lol, although you can heat both sides up fairly quickly and pull them out but you'll need to be quick .

Most of all just have fun whichever path you take hehe
solidcore is offline  
Old 03 October 2017, 22:12   #16
Cobe
Registered User

 
Join Date: Jan 2014
Location: Belgrade / Serbia
Age: 34
Posts: 518
haha will do
Cobe is offline  
AdSense AdSense  
 


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Similar Threads
Thread Thread Starter Forum Replies Last Post
Joypad that's 100% compatible with CD32 Joypad? ancalimon Retrogaming General Discussion 26 15 September 2015 09:49
CD32 Joypad picture Galahad/FLT Amiga scene 4 18 October 2014 21:30
How do I configure winuae to recognise left stick on joypad? RickDangerous New to Emulation or Amiga scene 11 23 March 2007 14:31
CD32 joypad narud17 New to Emulation or Amiga scene 12 06 December 2005 14:07

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +2. The time now is 06:35.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Page generated in 0.30901 seconds with 13 queries