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A comment on The Z80's feature discovered after 40 years [video]. Parent comment

Re:The Z80's feature discovered after 40 years [video] by II2II on Monday October 17, 2022 @08:27AM (#33232590)
Sure, but if memory serves me correctly, many early workstations used a microprocessor with an external MMU. It is misleading in the sense that it is not part of the Z80, but it is in the character of the times. (And MMUs are not the only CPU feature that was originally external. The FPU is an example that more people will be familiar with since it was an upgrade path available on many personal computers.)
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Re:The Z80's feature discovered after 40 years [video] by jandrese on Monday October 17, 2022 @11:19AM (#33234735)
I don't think MMUs were common on machines that ran on a Z80 however.
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Re:The Z80's feature discovered after 40 years [video] by DonHopkins on Monday October 17, 2022 @12:24PM (#33235827)
The home-brew pager (MMU) of the MIT-MC PDP-10 KL10 was appropriately called "KL-UDGE". (KL was the prefix of the PDP-10 model).

https://en.wikipedia.org/wiki/Kludge

It's on display at the Paul G. Allen Living Computer Museum.

https://sites.google.com/site/mthompsonorg/Home/pdp-10/pdp-1...

https://donhopkins.com/home/catalog/images/mc-console.jpg

Lars Brinkhoff has taken photos of KL-UDGE blinken lights panel and naked wire wrap boards:

https://twitter.com/larsbrinkhoff/status/1128601896619524097

>Photo 6/7: KL-UDGE lights panel

>Photo 7/7: KL-UDGE boards. Real-time time of day clock?

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Re:The Z80's feature discovered after 40 years [video] by wk_end on Monday October 17, 2022 @02:57PM (#33238030)
Was on display. The LCM closed due to COVID and there's no indication that it's coming back, sadly.
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Re:The Z80's feature discovered after 40 years [video] by 300bps on Monday October 17, 2022 @02:42PM (#33237866)
The Commodore 128 had an 8502 CPU, a Z-80 CPU and an 8722 MMU.

Was a pretty popular machine - sold 5.7 units worldwide. But probably only a tiny fraction actually used the CP/M mode that used the Z80.

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Re:The Z80's feature discovered after 40 years [video] by philistine on Monday October 17, 2022 @03:50PM (#33238662)
I don't know what's more concerning. The fact they only sold 5.7 units, or the fact someone managed to only buy .7 of a Commodore 128.
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Re:The Z80's feature discovered after 40 years [video] by otto2 on Monday October 17, 2022 @09:00PM (#33241720)
The sixth unit had CP/M disabled, so accountants wrote it down as 0.7 units.
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Re:The Z80's feature discovered after 40 years [video] by jandrese on Monday October 17, 2022 @07:17PM (#33240808)
Wow, I had no idea there was basically a second computer hiding inside of the C128. No wonder it cost so much.
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Re:The Z80's feature discovered after 40 years [video] by anticensor on Tuesday October 18, 2022 @10:38AM (#33247893)
Did you mean 5.7M?
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Re:The Z80's feature discovered after 40 years [video] by NegativeLatency on Monday October 17, 2022 @04:44PM (#33239290)
For example a Programmable MMU was an optional add on for the Macintosh II (which wasn’t a z80 but serves to illustrate the time when they began to become available to home computers)
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