Denial

Hi, pins are respectively 5-6 and 12-13. Thanks for the tip. Hi, More than 2V is High, but a good "1" level will be more than 3V. Remember that 7406 is "open collector" NOT gate, so the only measure that you can't find (or it is broken) is: input "1" output "1"...

Hi, here are some news for completeness: reading again the posts I realized that I didn't check the weldings as suggested by MCes, so I removed the board and did it (there are no signs of alterations). At that point I thought "ok you wanted the bicycle, then ride the bicycle": I wanted to ...

@ldxstx Do you have a good multimeter with continuity testing ? If so, check the small inductors between the serial port connectors and the board elelctronics to see if one is damaged. They are listed as LI3, LI4, LI5 and LI6 on the board. I tested all of them and they all work as expected, so as w...

Thanks eslapion for the suggestions! I have the multimeter and it can check for continuity: I'll do this in the afternoon. Meanwhile I tried "the software way" and there are interesting news: as you said this time I also tried to check the status OPEN15,8,15 INPUT#15,N$,E$,T$,S$ at this po...

Hi, here's the update (I confess that, loving so much these old "machines", I feel like I should wear a spacesuit whenever I open and touch their electronics). To make the story short: at last I found a socketed 6522, I swapped it with the other ones of the 1541, one at a time, trying all ...

Yes as written in my first two posts I've also tried with the other device numbers for a floppy drive. Thanks.
I'll try swapping the 6522 with some coming from my Vic20s, good idea
Cheers

In '82 me too :) In case of problems, just use this tool: http://style64.org/dirmaster (EDIT: sorry but it's not for .tap as far as I know; but you can use the Vice monitor: alt+m, s "filename.prg" 0 <start_address> <end_address> EDIT2: FinalTap is ok http://www.subchristsoftware.com/final...

Ok, so I will have to buy UB1, UA1 and UD3, since I've already tried the second connector and swapped the two 6522.
Unfortunately those chips aren't socketed as the two 6522, so desoldering-resoldering time is coming
Thanks for your help!
Enrico

Hi, I've found them here:
http://www.6502dude.com/cbm/vic20/arma/itaps.html

enjoy!
Enrico

P.S. welcome to Denial!

The only ICs that manipulate the serial signals are: UC3 6522 UA1 74LS14 UB1 7406 UD3 74LS86 So, being just these the "usual suspects" maybe it's better to get them as a replacement instead of investing time on the testing side. Has anyone all of them as spare parts to sell and send me? T...

Thank you! I have a multimeter and even an oscilloscope available: I will try to understand which kind of measurements I can do then, before buying parts that maybe are not involved. Your tips are immensely welcome since this is not my usual activity! :mrgreen: (boom!) Thumbs up, cheers :) Enrico

Hi Kakemoms, thank you for your reply and pointers :) I've been talking about the scrolling matter - and got useful tips&hints as always - with Mike and Nippur72; what I'm searching for at the moment, possibly, is some "crazy" buddy as me :P to specifically look into some asm portions ...

Thank you both for your answers! :) I did the following testing 1. C64 + 1541: same exact symptoms as the Vic 20: green led stays on (power), red one turns on at startup, then goes off; "DEVICE NOT PRESENT ERROR" after LOAD"$",8 (,9 etc) with no further red led nor motor activity...

Hi, I have a "new" 1541 and when connected to the Vic 20 it powers up normally: the red led stays on and then it turns off, while the green one remains lit. I can hear the motor spinning while the red led is on. The problem is that whenever I issue a command from the Vic, for example the u...

Hi, I am studying the disassembly of some games (i.e. Amok, Astro Panic, etc) to see instruction after instruction how they specifically implemented the scrolling at single pixel level, on the unexpanded Vic (at least for the moment I like to focus on this configuration). I am searching for buddies ...