Apple II

How do I do a horizontally scrolling sine wave in Applesoft BASIC?

Submitted by DistantStar001 on November 30, 2021 - 7:25pm

I tweaked this program from something I saw on the 8-bit Guy.  Managed to get the wave to fill most of the screen, repeat, and end where it begins on the screen.  However, I was wondering if I could get it to scroll horizontally across the screen? or draw from right to left? I don't know, I'm just playing with BASIC and wanted some pointers.

 

Program listing:

5 HGR

10 HCOLOR=3

20 FOR X=0 TO 278

30 LET Y=INT(-65*SIN(X*3.14/28))+70

40 HPLOT X,Y

50 NEXT X

60 GOTO 5

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Apple II

Floppy EMU Model C and CPM?

Submitted by gottj on November 29, 2021 - 6:36pm

Has anyone here tried to put a CPM image on the Floppy EMU Model C and successfully booted it with a softcard or applicard installed?

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Apple II

Digitek screenmaster 80 card

Submitted by AndyG001 on November 29, 2021 - 3:56pm

Hi everyone, has anyone ever come across the Digitek Screenmaster 80 column card for the Apple II ?

if so do you have any documentation etc ?

Cheers

Andy

 

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Apple II

TL866II-Plus and 74LS51

Submitted by tolderlund on November 28, 2021 - 8:48am

I have noticed that a 74LS51 (location C13 on a A2 board) always fails when testing with the TL886II-Plus logic IC test function.

Even if I take one from a working A2 board.

I am using the lastest software version 11.60.

Can anyone here try the same and see what happens?

 

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Apple II

Custom Enclosure - Floppy Emu

Submitted by PTB on November 27, 2021 - 9:15pm

Hi All,

 

I had an old Disk ][ case with nothing inside and I also had a floppy emu….. the result was inevitable :)

IMG_2880.JPG

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Apple II

Laser keyboard

Submitted by Wayne on November 25, 2021 - 5:14pm

I pulled a Laser 128 out of storage and while it has a qwerty keyboard, it types dvorak and I can’t seem to see a a switch for going back to qwerty. ??

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Apple II

Disk ][ Card Problem

Submitted by Clacri5 on November 23, 2021 - 6:08pm

Hello everybody.

Could someone please help me and give some hints ?

After years of unuse I am now restoring an old APPLE ][ plus, RFI Revision "D".  When I put in the DISK ][ Interface (650-X104-) it works, but I see some vertical lines on the screen. Have a look at the foto please. These lines become darker if the drive motor spins and are colmpletely gone if I pull out the interface.

I had to replace a few RAM chips (4116) and one ROM was gone but now, ROM, RAM and PROMS on the DISK interface all test good.

 

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Apple II

Disk II troubleshooting guide

Submitted by montreal on November 23, 2021 - 3:35pm

Does anyone know of working links to Disk II drive troubleshooting guides?

I found links in some forums here but they don't work for me.

My first Disk II drive is working great, I can create bootable disks with AdtPRO (great tool!).

The issue is with my 2nd Disk II drive which I recently bought on ebay:

1. When connected as the first drive, it will not read any disk. It powers on and just keeps spinning forever. I cleaned the drive head but it did not help. Worse, it seems to be erasing disks :-(

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Apple II

Apple ][ Plus Glitches? Also Diagnostic Software recommendations...

Submitted by DistantStar001 on November 23, 2021 - 1:57am

I have a 48k Apple ][+ with a Z80 and ROM switch card (with original Apple ][ ROMs installed on the card), however, I do not have a language card at the moment. The computer works for the most part, but every so often, it gives me some graphical glitches. It's usually fine for the first hour or so, but after a while, it would lose horizontal sync when I hit certain keys (mostly the space bar). The effects were temporary at first, but eventually, the picture would cut out completely or come back with random characters on the screen.

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Apple II

Apple II Europlus, vertical white bars on screen

Submitted by Pixelshift on November 21, 2021 - 8:59am

Hi all :)

 

First post - I have had an Apple II Plus (Europlus actually, I'm in the UK) in my loft for more years than I care to remember, and recently I've decided I am going to get it working, as well as some other 'vintage' computers such as a couple of C64s, VIC20s, Amigas, BBC Model Bs, etc. 

 

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Apple II

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