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General Category => NC100, NC200, PCW, PDA600 - the rest of the Family! => Topic started by: Starglider on 19:22, 09 September 18

Title: Amstrad light pen repaired + how they work in slow-mo
Post by: Starglider on 19:22, 09 September 18
You wanted more Amstrad content? Your wish is my command!

Ever wish you could see how Light Pens work in super slow-mo, through a high-speed camera? Ever wish you could watch an #Amstrad Light Pen being repaired? Call me the Genie of the lamp (pen). Welcome to Retro Recipes!
#retrogaming #retrocomputing
https://youtu.be/EBfkiprmoi0

Thanks!, Starglider aka ԹҽɾíƒɾɑϲԵíϲ's RҽԵɾ๏ RҽϲíԹҽs
️ http://youtube.com/perifractic
️ http://patreon.com/perifractic

Title: Re: Amstrad light pen repaired + how they work in slow-mo
Post by: robcfg on 23:16, 09 September 18
Cool video!


Glad you have your lightpen working again, and send our best regards to your puppy  :D
Title: Re: Amstrad light pen repaired + how they work in slow-mo
Post by: Bryce on 09:46, 10 September 18
Billisecond??? :D
milli - micro - nano - pico - femto - atto - zepto - yocto.

Good video otherwise.

Bryce.
Title: Re: Amstrad light pen repaired + how they work in slow-mo
Post by: Starglider on 09:50, 10 September 18
Cool video!


Glad you have your lightpen working again, and send our best regards to your puppy  :D
Thank you so much for your kind words! It means a lot to me. Puppy sends her regards.

Thanks!, Starglider aka ԹҽɾíƒɾɑϲԵíϲ's RҽԵɾ๏ RҽϲíԹҽs
️ http://youtube.com/perifractic
️ http://patreon.com/perifractic

Title: Re: Amstrad light pen repaired + how they work in slow-mo
Post by: Starglider on 09:52, 10 September 18
Billisecond??? :D
milli - micro - nano - pico - femto - atto - zepto - yocto.

Good video otherwise.

Bryce.
I put that in there just for you. My channel isn't aimed at scientists or electronics engineers, but everyday folk. Can you imagine if I started saying "yocto second" lol...

Cool comment otherwise

Thanks!, Starglider aka ԹҽɾíƒɾɑϲԵíϲ's RҽԵɾ๏ RҽϲíԹҽs
️ http://youtube.com/perifractic
️ http://patreon.com/perifractic

Title: Re: Amstrad light pen repaired + how they work in slow-mo
Post by: Bryce on 10:02, 10 September 18
Well admittedly, if you got anything electronic to react in a yoctosecond you would win a Nobel Prize. But micro and nanosecond should be known terms, even for non-electronic/scientific people.

Bryce.
 
Title: Re: Amstrad light pen repaired + how they work in slow-mo
Post by: Starglider on 10:26, 10 September 18
You raise an interesting question in isolating that one word from my Amstrad video for scrutiny...

Just how quick is the light pen and computer reacting...

Assuming a color HD screen that I was filming, it has 2 million pixels

x

60 Hz

=

124.5 million pixels per second

Microsecond?

Thanks!, Starglider aka ԹҽɾíƒɾɑϲԵíϲ's RҽԵɾ๏ RҽϲíԹҽs
️ http://youtube.com/perifractic
️ http://patreon.com/perifractic
Title: Re: Amstrad light pen repaired + how they work in slow-mo
Post by: Bryce on 10:47, 10 September 18
When you say "reacting", do you mean from the moment enough photons hits the lightpen until the computer sets a bit? To calculate this you would have to establish all the gates the signal is going through and then add up all their switching and latency times (which will vary from one chip to another, even when they are exactly the same type). That's how long the logic electronics would take to react, but the CPU and software are clocked, so they would take longer.

For a rough calculation: A typical 74LS part has about 10ns of latency (time it takes to switch the output from one state to another after the input has changed). So the number of gates the signal passes x 10 will give you the total signal time (roughly) in nanoseconds for the logic. Then add the delay due to the CPU and software which will probably bring you into the (low) millisecond range.


Bryce.
Title: Re: Amstrad light pen repaired + how they work in slow-mo
Post by: Gryzor on 15:02, 10 September 18
This should be very interesting. Not an entirely new subject, but I've never seen a video involving a CPC :)