Search found 73 matches

by C64Person
Wed Sep 09, 2020 10:48 pm
Forum: Help!
Topic: C64 With Black Screen
Replies: 138
Views: 7869

Re: C64 With Black Screen

Ok, this is all good to know. In this case, I will try to look for the best pricing options, but will favor 1571 if possible. I am not necessarily opposed to Newtronics, but as you said it seems they often have bad heads, so I would definitely only get one that has tested good. That's too bad about ...
by C64Person
Wed Sep 09, 2020 7:22 pm
Forum: Help!
Topic: C64 With Black Screen
Replies: 138
Views: 7869

Re: C64 With Black Screen

Alright, I will buy a new drive then. I was hoping to fix mine but I don't think that's possible. I'm new to this stuff, so do you recommend buying another standard 1541 like the ones I have (Newtronics 1541 with internal psu) or "upgrading" to a newer/possibly more reliable Commodore drive (1541-II...
by C64Person
Wed Sep 09, 2020 1:44 pm
Forum: Help!
Topic: C64 With Black Screen
Replies: 138
Views: 7869

Re: C64 With Black Screen

It runs two head bang cycles and then gives up when running the LOAD"*",8 command, which sounds like what you described as it failing to read and trying to reset itself. Running a format just brings the head back to track 0, where it does one banging cycle and then stops right there. The red light b...
by C64Person
Mon Sep 07, 2020 3:29 am
Forum: Help!
Topic: C64 With Black Screen
Replies: 138
Views: 7869

Re: C64 With Black Screen

I do get the flashing light when trying to access the drive, and the error is 21,READ ERROR,18,00. When trying to load from the drive, it does two head banging cycles before the red light begins flashing and FILE NOT FOUND ERROR is printed on the screen. Is it abnormal for the head to bang like that...
by C64Person
Sat Sep 05, 2020 9:16 pm
Forum: Help!
Topic: C64 With Black Screen
Replies: 138
Views: 7869

Re: C64 With Black Screen

Success! Well, sort of... I was swapping chips around between my two drive boards, and suddenly it worked! It turns out that UA1 in my primary board was bad, as swapping the chip in from my other board now allows the handshake to occur and the drive spins up when running a load command. Not sure why...
by C64Person
Thu Sep 03, 2020 1:42 pm
Forum: Help!
Topic: C64 With Black Screen
Replies: 138
Views: 7869

Re: C64 With Black Screen

I should be getting more input probes later this week. As I said before, I'm looking for some guidance on which pins I should be looking at to compare signals on U2 and UC3. I have no idea how I would find this, so hopefully you have some information on that!
by C64Person
Sat Aug 22, 2020 10:25 pm
Forum: Help!
Topic: C64 With Black Screen
Replies: 138
Views: 7869

Re: C64 With Black Screen

I only have 1 input probe for the oscilloscope right now, but I should have access to one within the next week, so once I get that I can give that a try. However, I 'm not sure how to find the corresponding pins on UC3, and I was able to figure out a few using the information you sent with the scope...
by C64Person
Thu Aug 06, 2020 10:20 pm
Forum: Help!
Topic: C64 With Black Screen
Replies: 138
Views: 7869

Re: C64 With Black Screen

Actually, it freezes when the drive is ON and plugged in; if the drive is off or unplugged from IEC, I do get a NOT PRESENT and READY message. I do have both C64’s and both have the same results all around, which is why I suspect the drive. Unfortunately, I can’t test because I have had no power in ...
by C64Person
Mon Aug 03, 2020 3:56 am
Forum: Help!
Topic: C64 With Black Screen
Replies: 138
Views: 7869

Re: C64 With Black Screen

The only pin I actually caught a signal on when running the program with 1541 on was pin 5. Interestingly, the signal seems the same as your image up to a certain point, where it just continues straight. It seems to me that this could indicate it behaving normally and then crashing when it stops fol...
by C64Person
Fri Jul 31, 2020 11:02 pm
Forum: Help!
Topic: C64 With Black Screen
Replies: 138
Views: 7869

Re: C64 With Black Screen

I have 2 drives, with one working mechanically (the other not) and the state of the 2 logic boards is not promising. One of the boards looks like it has had a good bit of repair work done (poorly), so I’m a bit less hopeful with that one, though they both yield the same result: a crash whenever tryi...