Apple II

Apple IIc memory chip replacement

Submitted by Giano on December 22, 2023 - 11:06am

Hello,

I'm planning to restore my Apple IIc and I've noticed that RAM chips are defective.

I've searched Internet to find these chips replacement, without any luck.

Any suggestions or pointers ? Ideally an European shop would be a plus. 

Heaps of thanks.

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Pineapple (clone) just let the smoke out

Submitted by softwarejanitor on December 21, 2023 - 4:59pm

I was playing with one of my clones, a Pineapple...  Unfortunately it "let the smoke out".  I had just booted the game "Ghostbusters" and was listing to the intro music when all of a sudden it got staticy and then PUFFFF!!! 

 

It appears that one of the differences between a Pineapple and an Apple ][+ is that it has a ULN2283B amplifier chip for the sound.  There is a volume knob on the back of the machine and I had the volume cranked and apparently that was too much for it.  The chip looks crispy.  Hopefully it is not an unobtanium item.

 

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Apple II+ 48k 6502 and/or rom issue

Submitted by LennyStudios on December 17, 2023 - 10:53pm

I have a 48k apple II+ with no expansion cards, and whenever I try to execute certain AppleSoft basic functions (HCOLOR, COLOR, PLOT, HPLOT, IF, FOR, LEFT$, just to name a few) it spits back a memory address at EC46 with different values depending on the function it didn't like. In monitor mode, when I run Ctrl+E to get the 6502 registers, it has the same values every time.

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Common capacitor failure? 16k ram card

Submitted by HiSir on December 16, 2023 - 6:42pm

16k memory ram card, had a capacitor smoke.   I had installed a new Apple II VGA card I had just assembled and was testing the machine.   I had considered leaving the top of the case open while I tested my newly built card but I didn't since I was running out of desk room.

 

I out the cover in and powered the machine on and my VGA card seemed to be working perfectly.  Although it didn't seem to work in 80 columns on my II+ but I am not sure of that is normal or not. I turned the machine off after about 10mins.

 

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Looking for assistnace with programming ATtiny2313

Submitted by Stargeezer on December 16, 2023 - 1:00pm

Howdy friends,

I am attempting to build Mike Willeal's keyboard ASC to PS2 Converter.  I finally overcame the battle of the Gerber files but had to use PCBWay instead of my usual PCB fab company, OSH Park.  While waiting for the PCB to arrive, I wanted to start programming the ATtiny2313. 

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Formatting preformatted IBM disks

Submitted by HiSir on December 5, 2023 - 9:18am

I was using ADT PRO and having trouble formatting disks that are IBM formatted.  ADTpro won't let me do it. Always getting IO errors. 

 

I used a magnet on a preformatted IBM disk and it seemed to work after that.

 

I tried init hello on a prodos version but it must have been too old, and I tried a newer DOS version and it complained I didn't have an enhanced IIe, as I only have a IIe non-enhanced.

 

Is there a way to format IBM formatted disks? 

 

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apple IIGS power supply question

Submitted by pcbishaf on December 1, 2023 - 10:03pm
The power connector on the motherboard, J14, is measuring -11.4 volts when it should be -5V
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UNCLE BERNIE'S TIMING HAL SUBSTITUTE

Submitted by UncleBernie on December 1, 2023 - 9:56pm

Hi fans -

 

today I made some progress with substituting the timing HAL of the Apple IIe and IIc.

Here is what happened so far:

 

Weeks ago I took the equations from Jim Sather's book and plugged them into my PLD design software.

I then turned loose my proprietary PLD test and analysis tools on the JEDEC, and got lots of automatically generated test vectors.

Alas, when I took that JEDEC file to a programmer, and ran its test vectors against a real HAL (Apple part #341-0710-A date code 8429) plugged into it, I got hundreds of vector fails.

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Videx softswitch fab

Submitted by warby on November 30, 2023 - 5:26pm

Hi all,

I'm making my own Videx softswitch. I have the 80 col card in  my ][+ and it works great with a pushbutton A/B switch but I don't have a softswitch. I've seen them on eBay but I think it would be fun to make my own (I etch my own PCBs). I saw a PCB design on Github but I have a slightly different design in mind.

I see the schematic in the manual and it's pretty straightforward:

 

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Apple II plus questions

Submitted by HiSir on November 29, 2023 - 12:50am

I am awaiting delivery of this Apple II plus.

 

I have a IIE but don't know much about the II Plus.

 

1.  What were the purpose of the holes drilled in the bottom of the case?

2. I see it has a 16k memory card by COEX.  Is this only a memory board and not a language card?

2a. Is a language card beneficial to have?  I used to have one but I sold it thinking I didn't need it for a IIe.

3. Should I assume this unit has 32k of memory?

 

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