No way to boot an Apple IIe PAL...

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No way to boot an Apple IIe PAL...
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Hi mates

I am New on the forum and i am from Spain. I want to disclaim for my English but i hope it could be good enough to be undestood.

I am the owner of two Apple ii computer since not much time, but i love computer since a long time ago. I use to repair many kind of electronics and electric machines and i have experience repairing with pc computers.  i am quite new on apple machines but very interested on them.

 

The working Apple ii machine is a portuguese keyb one, and has the most of the chips o shokets. the not operative one is an spanish keyboard one.The main problem is that is not booting but it shows some vertical lines and spots on screen. I use the same screen and power supply with both machines.

the not good one is not making any sound at booting and has all the ic on sokets. i have swaped all the ic with the good one and the worked well.

I have electronics knolage and i can use an osciloscope to test what you want. the Quarz cristal are working well and i can see the 1mhz signal on the right pin of the 6502 and it generate the two amplified clock signals too.

 

I have upload a picture but not sure if it will apear here...

 

I need you help to put this machine to work. Thanks mates.

 

 

 

 

 

 

 

 

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Firmware Diagnostic first

There is a built-in diagnostic that can be used as a pointer to where the problem may lie.

First remove any disks in connected disk drives, then hold down both "Apple" buttons and press Reset.

The diagnostic works differently depending on whether the Apple IIe is "Enhanced" or not, which you can verify by checking if the CPU is a 6502A (not Enhanced) or 65C02 (Enhanced).

Interpreting the result of the diagnostic depends on what is displayed on the screen, how many beeps the speaker makes in what order, and understanding the flow of the diagnostic program. The book "Understanding the Apple IIe" by James Sather is helpful for this (See 10-6 in the book). That book also has advice for troubleshooting using an oscilloscope, multimeter, etc. The PDF is easily found online.

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Hi robespierre  Thanks for

Hi robespierre 

 

Thanks for your advice. I will read the book you are talking about but fist i have tried with reseting with two apples botton pressed.

I had some diferences on the screen and some noices from the speaker but not beeps at all. In the good machime y get the kernel ok message as spected...

When i do a single reset i can see some changes too but antthing else.

 

Thanks.

 

 

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Last seen: 1 month 1 day ago
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Here again. I have a good

Here again.

 

I have a good boot at the moment, with a beep and executing any instruction, but no image on screen. I had bad contact on some ram chips so i took out the sokets and now 3 ram chips are soldered directly on the mainboard.

 

I need help to continue with the restoration becouse now i have a video issue. I write GR + enter after the boot and the graphic mode change. The i write TEXT +enter and it change again to text mode but now i see some lines on screen. I spected to see many @ characters and the the prompt but just have lines.

 

Any idea to solve this?

 

Thanks

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Yikes.  I would never solder

Yikes.  I would never solder a RAM chip to a motherboard.  I would have put in a new high quality socket.

 

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Yep for sure i will but first

Yep for sure i will but first i want to ensure a good contact betwen the board and the chip...

 

 

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