Re: The Cosmic Puppet's Universe.
Posted: 25 Jun 2022 00:09
These are quite short which might work jewellery wise. Any idea what the circles are for? Wondering if they could be used as an attachment point on the back-side.
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Never thought about it :lol: Assume used as alignment points for assembly machines.Cosmic Puppet wrote: 25 Jun 2022 00:09 Any idea what the circles are for? Wondering if they could be used as an attachment point on the back-side.
What's a mask rom?exxos wrote: 25 Jun 2022 00:17Never thought about it :lol: Assume used as alignment points for assembly machines.Cosmic Puppet wrote: 25 Jun 2022 00:09 Any idea what the circles are for? Wondering if they could be used as an attachment point on the back-side.
Still don't get why Atari used those mask roms over eproms. Unless they were simply cheaper.
Those ROM chips are.. One time programmable.. Eproms had a little window so you could erase them.. Is assume they be more common and mass produced and cheaper.. But couldn't have been.
Usually "Mask ROMs" use the technique of setting the content of the ROM during chip manufacture, using one of the optical "masks" to encode the data.exxos wrote: 25 Jun 2022 00:34Those ROM chips are.. One time programmable.. Eproms had a little window so you could erase them.. Is assume they be more common and mass produced and cheaper.. But couldn't have been.
Cool.stephen_usher wrote: 25 Jun 2022 12:19Usually "Mask ROMs" use the technique of setting the content of the ROM during chip manufacture, using one of the optical "masks" to encode the data.exxos wrote: 25 Jun 2022 00:34
Those ROM chips are.. One time programmable.. Eproms had a little window so you could erase them.. Is assume they be more common and mass produced and cheaper.. But couldn't have been.
Once the costly process of making the original optical mask is done the price per unit for a large batch is small as after the wafer is produced there's only the standard chip testing and encapsulation to do. There's no separate, and expensive, programming step involved.
Yep. Individual transistors are large. In a IC you can have zillions of them in there.Cosmic Puppet wrote: 25 Jun 2022 12:21 I was also thinking this morning is an IC just miniature version of a circuit?
I don't understand all that technical stuff but I can see now why the first computers were so large.exxos wrote: 25 Jun 2022 12:29Yep. Individual transistors are large. In a IC you can have zillions of them in there.Cosmic Puppet wrote: 25 Jun 2022 12:21 I was also thinking this morning is an IC just miniature version of a circuit?
Its why PLDs are cool. Like GAL chips. If a circuit was built out of logic chips it could he large and a pain to make corrections. So being able to put gates inside a single GAL chip means instead of track cutting and bodge wires, you fan change it all in software.
EG if you had 2 buffers in series, they could be in 1 logic IC. But oh crap now you need a buffer and inverter, so you have to bodge a extra chip on the PCB. In a GAL you can add a inverter in seconds. No PCB changes needed. Being able to do custom logic is a huge saving in logic chips and PCB space. Your PCB is basically in software.