C128 power on problem

[MIRKOSOFT]

Hi!

I have problem with starting Commodore 128DCR.

At power on show no picture (40 col/80 col mode), only on the left side vertical line with color of border.
When computer runs, correctly starts CassAdapt, RAMLink SWAP buttons working, but diskdrive 1581 at #8 boots not, hangs.
One thing which I don't understand not in the least tick with low volume of computer during is turned on...

I tried I think all what I could:
disable/remove RAMLink, enable/disable JiffyDOS, internal EPROM of BASIC 8/GEOS 2.0 switching, removing CassAdapt, removing 40col cable/ 80 col cable, turn off 1581, change PSU cable, remove all serial devices...

CAN ANYBODY HELP ME?

Many many thanks for every advice...

Miro

[MIRKOSOFT]

Hi!

So, I did some tests.
I replaced JiffyDOS KERNAL with original German.
I changed internal 1571CR drive with other one (sure working).
I tried to remove EPROM from MB socket.
----
And:
JiffyDOS/Original KERNAL is ok - both the same behavior.
Internal 1571CR is the problem with tick - after power up searches data on 5,25" diskette (similar to hanging on 1581)
EPROM in socket is OK.

So, what can be problem?

Else again many many thanks for every advice.

Miro

[MIRKOSOFT]

I'm not sure if I think good, but it seems like "hang on" whole computer.
'Cause 1571CR built-in hangs too, not only 1581...

?

[MIRKOSOFT]

I'm not sure: THE SAME PROBLEM I HAD ALSO ON COMMODORE128DCR WHICH I HAVE IN ROOM DISCONNECTED...

I don't know what happens, but had no help... so, I bought new one - I DON'T WANT TO BUY NEW ONE AGAIN...

PLEASE HELP ME ANYBODY!!!

Maybe I give as a gift the C128DCR which is still here in room...

Many thanks and all hopes

Miro

[RobertB]

PLEASE HELP ME ANYBODY!!!

Maybe I give as a gift the C128DCR which is still here in room...

If you yourself cannot repair it, you must give it to a qualified technician who can repair it, someone like Ray Carlsen.

          Back from the Amiwest Show,
          Robert Bernardo
          Fresno Commodore User Group
          http://videocam.net.au/fcug

[MIRKOSOFT]

problem is not repairing - problem: what is wrong?

[RobertB]

problem: what is wrong?

Since you cannot determine what is wrong (and neither can we), then an expert technician must be consulted, a technician who can actually try out your equipment by running tests on it, a technician who has had years of experience and who has the proper diagnostic devices.

          Otherwise, you would just be guessing,
          Robert Bernardo
          Fresno Commodore User Group
          http://videocam.net.au/fcug

[MIRKOSOFT]

Please look at this:


http://www.forum64.de/wbb3/board13-sonstige-commodore/board95-c128/39620-c128-power-on-problem/#post466614


Is it possible? 8701 timing chip fail?

[dr.v]

Miro, get yourself a C128 diagnostic cartridge from ebay.  It will cost you about $20.  It's worth having for situations like you find yourself in.

Tom

[RobertB]

Miro, get yourself a C128 diagnostic cartridge from ebay.

The diagnostic cart should also come with the specialized cable(s) that connect the cart to all the ports of the C128.  Best would be the diagnostic cart with cables which reads the condition of the computer without the need of a video display, i.e., it shows the condition of the computer by a number of LEDs on the cart.

          Portland's Jim Scabery has one; I have one somewhere in storage,
          Robert Bernardo
          Fresno Commodore User Group
          http://videocam.net.au/fcug
          The Other Group of Amigoids
          http://www.calweb.com/~rabel1/
          Southern California Commodore & Amiga Network
          http://www.sccaners.org

[MIRKOSOFT]

is it this:

http://cgi.ebay.com/NEW-Commodore-128-Diagnostic-Cartridge-CBM-785260-/310264783104?pt=UK_VintageComputing_RL&hash=item483d38e100



or


http://cgi.ebay.com/COMMODORE-64-128-dual-diagnostic-cartridge-/300484083776?pt=LH_DefaultDomain_0&hash=item45f63f4040


Miro

[dr.v]

Yes, Miro that is the diagnostic cartridge to which I was referring. 

[MIRKOSOFT]

OK, I bid.


But here's one Q:


When I don't have any video output how to diagnose C128DCR?


Many thanks.


Miro

[RobertB]

When I don't have any video output how to diagnose C128DCR?

Uh, reread my post on the best diagnostic cart.

          Truly,
          Robert Bernardo
          Fresno Commodore User Group
          http://videocam.net.au/fcug
          The Other Group of Amigoids
          http://www.calweb.com/~rabel1/
          Southern California Commodore & Amiga Network
          http://www.sccaners.org

[MIRKOSOFT]

I had to read, but where to find one?

[dr.v]

Miro - start your search here: http://www.commodore128.org/index.php?topic=3567.0.  Robert mentioned that Jim may have one available.

These forums contain all kinds of useful information.  Just read the posts carefully, and do some searching.  You will eventually find what you need.

Tom

[RobertB]

Robert mentioned that Jim may have one available.

Jim has one, but he's not selling it. 

          Truly,
          Robert Bernardo
          Fresno Commodore User Group
          http://videocam.net.au/fcug

[guayar]

Hi,
I have similar problem. When I'm trying to power on C128DCR I get black screen or some weird characters like @ and chess board all over the screen. One attempt on about 30 I get lucky and C128DCR boots correctly. Can anybody can help what is causing it?

[MIRKOSOFT]

Hi!


My C128DCR at power up shows only blank black screen with one horizontal non-stable line on left side in VIC mode, VDC mode shows nothing. So, no characters and hanging at first found drive reading...


I solved this problem that I bought new one C128DCR... it's not ideal, but I'm not so good in electronic, so there was not choice... but - still awaiting by post my C128DCR...


Miro

[XmikeX]

Gentlemen,

My experience with DCR is limited, but my memory is recalling issues like these on my flat C-128s oh-so-long-ago (and I own nine flat units).  I had maybe three/four of these turn temporarily bad, as described in this thread earlier, due to a very simple problem : Gumming up of the On/Off Switch.

Temp Fix : disconnect power supply, toggle on/off switch rapidly 20-30 times, reconnect power supply - turn on c-128.

Perma Fixes : 1) clean the switch (disassemble switch, clean switch, reassemble switch) and/or 2) replace switch.
--

There may be a chance of this relatively-simple switch issue being relevant to this thread, but proper testing is highly recommended.

By the way, the above Switch Nonsense was the only troubling issue I ever had with flat C-128s, aside from the usual keyboard failures and one incidence where roms had unseated themselves after thermal cycling.. (wow, the myths were right on that one!).

XmX