Random characters "only" with fast reboot.

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Random characters "only" with fast reboot.

Hello!

Today I did my first boot and on my Apple-1 replica. Everything looks ok! Clear and reset also. (Don't have keyboard yet to test farther).

 

What i saw is, when i do fast reboot (switch off/on) in place of "@" I get random or missing characters at boot screen. Clear and reset works ok.

But if I leave my replica off for 3-4 minutes and switch it on after that time, boot screen is working great.

 

Is that normal?

 

Thank you! 

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Joined: Jun 18 2010 - 13:54
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Yes. Apple II's do it too.

Yes. Apple II's do it too.

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Thank you for your answer

Thank you for your answer.

From a technical point of, why that happens?

 

 

 

 

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RAM chips can be left in

RAM chips can be left in funky states if power is switched on and off quickly.

 

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I see, thank you!

I see, thank you!

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More importantly, it's the

More importantly, it's the fact that the Apple-1 (and the non-autostart Apple II) do not have a Reset routine that would normally clear the screen. So you are left seeing whatever contents the Video RAM has when first switched on. The Autostart ROM in the Apple II also suffers from this as well since it relies on two memory locations to distinguish between a warm start and a cold boot. These locations can often survive a power cycle leading to incorrect booting.

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Great! Now I understand very

Great! Now I understand very well. Thank you!

 

 

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