Search found 1318 matches

by srowe
Mon Mar 25, 2024 1:43 am
Forum: Hardware and Tech
Topic: Building a quality PSU
Replies: 3
Views: 174

Re: Building a quality PSU

Orangeman96 wrote: Sun Mar 24, 2024 8:56 pm I just got a custom PSU from Ray Carlsen that services both versions of the VIC-20 and the C= 64; suffice it to say I LOVE it! -OGM
I believe Ray has retired now.
by srowe
Sun Mar 24, 2024 7:08 am
Forum: Hardware and Tech
Topic: Building a quality PSU
Replies: 3
Views: 174

Re: Building a quality PSU

I've just remembered I had a homemade PSU at the back of the cupboard.
psu.jpg
The LM340 is rated at 1.5A, I wonder if I could replace that with an LM323 to increase that to 3A?
by srowe
Sun Mar 24, 2024 5:53 am
Forum: Hardware and Tech
Topic: Building a quality PSU
Replies: 3
Views: 174

Building a quality PSU

While I have a number of original "bricks" I'm well aware that they can suffer from catastrophic failure (I've just scrapped one that put out 9V to the 5V terminals). I'd like to make a bench supply, suitable for both the VIC and C64. There are many cheap 5V PSUs available but I think I'd ...
by srowe
Thu Mar 14, 2024 8:40 am
Forum: General Topics
Topic: modded VIC 20 kernals?
Replies: 14
Views: 569

Re: modded VIC 20 kernals?

Overdoc wrote: Thu Mar 14, 2024 7:18 am Another idea that just came to my mind would be a modified kernal, which makes the VIC20 compatible with a 1541 drive?
There's no compatibility problem between the VIC-20 and a 1541. The UI+/- allows you to recover the transfer speed loss that had to be added for compatibility with the C64.
by srowe
Thu Mar 14, 2024 3:42 am
Forum: General Topics
Topic: modded VIC 20 kernals?
Replies: 14
Views: 569

Re: modded VIC 20 kernals?

Without adding some form of bank-switching you would have to remove some functionality (as JiffyDOS does). That then prevents you from switching it while the computer is running. There's too much code that presumes it can use any part of the KERNAL, not just the public entrypoints, having any altern...
by srowe
Sun Mar 03, 2024 10:20 am
Forum: Emulation and Cross Development
Topic: VIC listing program
Replies: 5
Views: 228

Re: VIC listing program

Hello all, Though I've quite literally just joined Denial -- I only found it today -- I've been a VIC user on and off for all of my life. (Quick intro: my parents bought me one, brand new, back in 1981 or thereabouts, when I was... ahem... younger than I am now.) Well, here I am. And I wanted to be...
by srowe
Sun Mar 03, 2024 6:57 am
Forum: Programming
Topic: Screen Management
Replies: 3
Views: 295

Re: Screen Management

Starting from the decimal address 7680 (initial part of the screen), and having 22 columns x 23 rows, I would have a total of 506 bytes to write. Now if for example I used: LDX [screenData] STA $1E00,X and I made a cycle, the value of X could not be higher than the fateful 255, so how can I write t...
by srowe
Thu Feb 22, 2024 2:30 am
Forum: Games
Topic: German Magazine - Type-Ins - Compute Mit
Replies: 133
Views: 33402

Re: German Magazine - Type-Ins - Compute Mit

Richard has this magazine series in his Listings Archive

http://www.vic20listings.freeolamail.co ... mpmit.html

But there are a couple of programs not there (GRAPHOLOGIE and SUPER-RALLYE?). Perhaps you could send them to him to include?
by srowe
Wed Feb 21, 2024 12:50 pm
Forum: Emulation and Cross Development
Topic: Emulation of RS232 VIC20 for running multiplayer games
Replies: 34
Views: 10838

Re: Emulation of RS232 VIC20 for running multiplayer games

Why are pins B and C jumpered? Is it so that an interrupt is raised when data is received along PB0? I haven't looked at mimmosic's code yet, but I'm guessing that CB2 will be set to HANDSHAKE OUTPUT MODE for this to work? Correct, the receive line must be connected to both CB1 and PB0 so that a in...
by srowe
Sun Feb 18, 2024 3:34 am
Forum: Programming
Topic: "Free ZP" which ones?
Replies: 6
Views: 243

Re: "Free ZP" which ones?

coming from Atari 800 and C64 I am used to switch off OS completly and having the ZP "free". on the VIC20 I can not do this but using the IRQs mainly so just to be sure. what are the ZPs which are really free? :) There are very few locations that are completely unused $2A $52 $FB - $FE Th...
by srowe
Mon Feb 12, 2024 12:52 pm
Forum: Collecting and History
Topic: How to convert Tap files to D64?
Replies: 11
Views: 297

Re: How to convert Tap files to D64?

Standard (i.e. without a fastloader) .tap files can be converted to d64 using my command line tool

https://cbmshell.readthedocs.io/en/latest/index.html

As Mike points out, if the code tries to chain load another program, read data files etc that needs to be fixed up manually.
by srowe
Mon Feb 12, 2024 1:49 am
Forum: Collecting and History
Topic: 5 Ultra-Rare Games by "Aim Software"
Replies: 7
Views: 309

Re: 5 Ultra-Rare Games by "Aim Software"

A couple years ago I posted several ALA Software games and a member was able to generate the entire list in a D64 file. That would be awesome if somebody again could lump them all in one D64 file. I think this is the thread you mean https://www.sleepingelephant.com/ipw-web/bulletin/bb/viewtopic.php...
by srowe
Sun Feb 11, 2024 8:27 am
Forum: Emulation and Cross Development
Topic: Corrupt end of basic program
Replies: 7
Views: 263

Re: Corrupt end of basic program

Have you got a short BASIC loader program that then chains a longer BASIC program? This combination causes the end of the second program to be overwritten by variables, in this case the start of variables (VARTAB) is not updated.
by srowe
Fri Feb 09, 2024 12:23 pm
Forum: Programming
Topic: "Ultimate Expansion" - new firmware for FE3
Replies: 58
Views: 9601

Re: "Ultimate Expansion" - new firmware for FE3

The IRQ clock, i mean could be placed under the normal screen. And of course with an alarm set and alarm tone. Taking over the IRQ once you've left the FE3 menus would be tricky. If you enter BASIC it would work ok until you wanted to run a program. It certainly wouldn't behave well if you launch a...
by srowe
Sat Feb 03, 2024 8:43 am
Forum: Emulation and Cross Development
Topic: Keyboard Buffer and Ctrl/Shift/CBM etc
Replies: 20
Views: 899

Re: Keyboard Buffer and Ctrl/Shift/CBM etc

SparkyNZ wrote: Sat Feb 03, 2024 8:12 am Right, so this is the result of the CRNCH routine?

Code: Select all

89 20 31 30 00
Correct.
Probably pay me to step through that routine and dump that piece of memory as it goes
Using the monitor in VICE is a good way of understanding how this all works.