>> It's the 6510, which is similar to the 6502 that everything else used
>> but with a few minor alterations. It's not a C64-specific chip though;
>> just a different model in the range.
>>
> 
> But, see, it isn't an off-the-shelf component.

How do you figure that?

MOS Technology made the very successful 6502, so they designed an 
upgraded version, the 6510. It just so happens that Commodore purchased 
the 6510 for their Commodore 64 system. How is that not "off-the-shelf"?

>> This is the part I don't get. Mounting more chips on a board costs
>> money, but making an ASIC costs orders of magnitude *more* money.
> 
> I think part of the ASIC cost could be design, though. Whereas with 
> discrete gates you don't have to design them at the transistor level, 
> but with a custom IC, they must be designed at the transistor level, and 
> it becomes critical to consider the analog electrical characteristics of 
> the circuit layout, so it takes a fair bit more work. Judging by the 
> other posts I've read, the cost isn't in the fab. Which is surprising, 
> given the clean-room requirements and high-resolution photo-etching 
> process.

Fabricating a 40 nm Intel Core i7 might require high-resolution 
photo-etching such that the fab itself is expensive. If you're just 
throwing a few logic gates together, you won't be using a 40 nm fab. So 
the fabrication costs are quite small; it's setting up the production 
line that costs $$$. And, of course, the design costs. But I would 
imagine tooling up a fab is astronomically expensive. If you aren't 
making 80,000,000 units, it would seem prohibitively expensive.

>> More like, they know their clients need a shaker that's guaranteed to
>> work repeatably, so they can charge anything they like.
> 
> I'm sure there's a point where the cost would be more than the client 
> will accept.

You wanna bet?

> But it takes good engineering and attention to detail to 
> get a machine that operates repeatably with high accuracy and precision.

I wouldn't mind, but most of these devices don't even work very well...

>> It connects to a PC via
>> GPIB. (No, I've never heard of it either.)
> 
> Not heard of GPIB, so I looked it up. Apparently aka IEEE-488 surprised 
> they're not using Ethernet or something less obsolete... but, there you 
> go. ;)

Well, the newest mass spectrometer we have was purchased about 5 years 
ago. (Second-hand, obviously. We can only afford to buy the old crap 
that other companies are throwing away.) Still, I gather GPIB is 
supposedly quite popular in scientific applications. (Could explain why 






>>> Maybe not, but they probably have some logic somewhere outside of the
>>> CPU to manage signals, enable and disable drives, and such.
>>
>> You don't just do it all in software? That sounds much cheaper...
> 
> You still have to have the hardware to execute the commands of the 
> software, and depending on the application it could be much more 
> reliable to have it done in hardware.

If all you're doing is cycling stepper motors, it would seem that all 
you need is some memory-mapped registers and the analogue electronics to 
map a binary digit to a step signal.

> Some things safety related are not 
> controlled by software at all... Take the Emergency Stop on industrial 
> machines, for instance ...

Then again, that's an extremely simple function.

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