Search found 14 matches
- Thu May 18, 2023 5:52 pm
- Forum: Buy, Sell, and Trade
- Topic: Wanted 6560 VIC chip
- Replies: 1
- Views: 4950
Wanted 6560 VIC chip
I know they're getting harder to find, but I have to ask if anyone has one. I have a dead VIC-20 and everything else tests good (swap testing).
- Sat May 13, 2023 9:00 am
- Forum: Hardware and Tech
- Topic: Mega-cart issues?
- Replies: 13
- Views: 5787
Re: Mega-cart issues?
What should I be expecting? /RESET is active low, so upon either a press on the Mega-Cart reset button, or leaving the Mega-Cart menu into a game/tool or the BASIC start-up prompt you should see a low level pulse (less than 0.8 Volts) on the order of maybe 10s of milliseconds, and a high level sign...
- Fri May 12, 2023 11:43 am
- Forum: Hardware and Tech
- Topic: Mega-cart issues?
- Replies: 13
- Views: 5787
Re: Mega-cart issues?
... Do you have any means to monitor the reset line on the cartridge port (pin X)? Yes, I have a Rigol DS1202Z scope. What should I be expecting? And funny how you mentioned the reset, because I forgot until just now. The physical reset button the cart actually doesn't work. I wonder if they're rel...
- Fri May 12, 2023 6:38 am
- Forum: Hardware and Tech
- Topic: Mega-cart issues?
- Replies: 13
- Views: 5787
Re: Mega-cart issues?
I've not necessarily written off that it could be a faulty connection in the VIC. After all, these things are ~40 years old. I did spray it with contact cleaner and also used a fine grit sandpaper to to try "polish" the contacts. But I've tested pretty much every other cart I have (half do...
- Thu May 11, 2023 11:39 am
- Forum: Hardware and Tech
- Topic: Mega-cart issues?
- Replies: 13
- Views: 5787
Re: Mega-cart issues?
You can try unzipping and running the attached mega-cart repair program on the Vic. Can't remember where I got it, but it has rescued mine a couple of times. Thanks for the repair program. Unfortunately, when I say "nothing works", I mean that literally. I can't even get the VIC to load u...
- Wed May 10, 2023 10:42 am
- Forum: Hardware and Tech
- Topic: Mega-cart issues?
- Replies: 13
- Views: 5787
Re: Mega-cart issues?
Firstly, you need to enter the Service menu. In order to enter this menu, hold down the CTRL key when you turn ON or reset the Vic-20. Look, I'm not trying to be snippy, but since you didn't read my post, you will see that the second photo shows what happens when I try this, e.g., it does not work....
- Wed May 10, 2023 8:05 am
- Forum: Hardware and Tech
- Topic: Mega-cart issues?
- Replies: 13
- Views: 5787
Mega-cart issues?
It's been a long time since I played with my VIC-20, so I broke everything out and wanted to dive right in with the Mega-Cart. But I seem to be having issues... When I select an image, it never loads and just sits there forever. It does matter which image, or what kind (tape or cart), it never actua...
- Sat Jul 13, 2013 3:35 pm
- Forum: Hardware and Tech
- Topic: Digital Interface Systems 16k RAM expansion
- Replies: 4
- Views: 1260
Digital Interface Systems 16k RAM expansion
I recently acquired a "Digital Interface Systems" 16k RAM expansion, in the infamous "unknown condition". It has eight 6116 RAM chips (2k by 8 bit), a TTL decoder (74xx139) and two banks of DIP switches (one is 8 switches, the other is 2 switches). I took the dare and plugged it ...
- Sat Nov 24, 2012 12:01 pm
- Forum: Games
- Topic: IFR manual
- Replies: 1
- Views: 824
IFR manual
Hi everyone, I recently picked up a cart for IFR (instrument flight rules, a flight sim), and wanted to find a manual for it, or a scan of the manual. So far, all I have found is ROM dumps. The author released copyright on this a number of years ago, but I figured the original cart was a nice additi...
- Thu Oct 25, 2012 7:54 am
- Forum: Buy, Sell, and Trade
- Topic: Looking for replacement keycaps
- Replies: 3
- Views: 1171
- Fri Oct 19, 2012 6:43 am
- Forum: Buy, Sell, and Trade
- Topic: Looking for replacement keycaps
- Replies: 3
- Views: 1171
Looking for replacement keycaps
I am looking for replacement keycaps for the original PET-style keyboard, most specifically, the numeric keys 1 thru 0. Pretty much open to any variation that would net me replacement keycaps (busted up keyboard, shell, etc). But I'd would like to avoid buying a working VIC just to scavenge it for t...
- Tue Sep 25, 2012 2:14 pm
- Forum: Hardware and Tech
- Topic: Dead VIC
- Replies: 5
- Views: 1816
Replace all the chips! To which he replied, quoting the original message: Yes, I've tried all the socketed chips, including the 6560 aka the VIC. I have a handful of 555's in shipment, I'll plan to try that first, and it's also easier to replace... I can hopefully dig up an LS02 in my pile as a bac...
- Tue Jul 10, 2012 6:36 am
- Forum: Hardware and Tech
- Topic: Dead VIC
- Replies: 5
- Views: 1816
- Sun Jul 08, 2012 10:56 am
- Forum: Hardware and Tech
- Topic: Dead VIC
- Replies: 5
- Views: 1816
Dead VIC
Hello all, I (like so many others, I see) have a dead VIC-20 which I would like to bring to life. I'd like some specific suggestions which I'll list below, but for starters, what I know is this: This is an older (2 prong) NTSC system. The power brick tests ok. The rating on the brick states 10vac, a...