Port system documentation updated

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Black_Cat
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Re: Port system documentation updated

Post by Black_Cat » Sun Jan 20, 2019 8:45 pm

varmfskii wrote:
Sun Jan 20, 2019 8:00 pm
Say, I want the value in a register other than A, especially if I want to preserve A.
Once the rules are written, and embodied in the hardware, these rules should be executed, otherwise the software will not work correctly. You can break existing rules if you don't care about your reputation. You have the freedom to drive as you please, but nevertheless you are driving in accordance with the rules of the road. You have the freedom to pour gasoline into a diesel engine, but still you don't. :) There is no absolute freedom. :)

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varmfskii
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Re: Port system documentation updated

Post by varmfskii » Sun Jan 20, 2019 9:09 pm

Black Cat: there is not only one correct solution!!! If the rules don't yet exist you aren't breaking them.

We can freely restrict to in a,(nn) because that is the only reason the way to access the port.

You can't access the port with other than in a, (nn) because it breaks the rules.

Can't you see the contradiction. Are you stupid or are you trolling.
Backer #2741 - TS2068, Byte, ZX Evolution

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Black_Cat
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Re: Port system documentation updated

Post by Black_Cat » Sun Jan 20, 2019 9:21 pm

No problem. You have the opportunity to offer a better way how to separate Kempston mouse and Kempston joystick. :)

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varmfskii
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Re: Port system documentation updated

Post by varmfskii » Sun Jan 20, 2019 9:34 pm

The ZX Next's ability to enable and disable peripherals combined with a priority system for port collisions seems a reasonable solution.

The problem is that you insist on the notion that any solution that doesn't use A16 is broken. It is just different. The ZX Evolution a exUSSR machine allows for setting up full port decoding (I forget whether that is in baseconf or TSconf) obviously there are people in the east who have decided that A16 is not a panacea.
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