Re: Zilog stopping Z80 production

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Sujet : Re: Zilog stopping Z80 production
De : dk4xp (at) *nospam* arcor.de (Gerhard Hoffmann)
Groupes : sci.electronics.design
Date : 27. Apr 2024, 13:57:05
Autres entêtes
Message-ID : <v0ip6h$1tn2$1@solani.org>
References : 1 2 3 4
User-Agent : Mozilla Thunderbird
Am 27.04.24 um 12:39 schrieb albert@spenarnc.xs4all.nl:

Motorola was much better in this respect. Peripherals are accessed
by handshake. So you could  put a longer delay iff the peripherals
are slow.
 I remember spending 2000 guilders in around 1980 for 16 K ram
for my Z80.
Just to discover that code in this ram couldn't run, because the
Z80 was too slow. Only useable for data.
The other way around. The RAM cycle time was too slow for the
Z80 because of the DRAM refresh cycle after the instruction fetch.
And there was a /wait input on pin 24 if your bus logic was
unable to keep up with the Z80. Looks like handshake for me.
My first 64K*1 DRAMs did cost DM 64,00 each - which was quite a
sensation (NEC or Hitachi). And of course, my system got
the the first usable 8" DSDD floppy drives and ran CP/M.
I'm pretty sure that the instructions were in DRAM.
There was no ROM after booting at all.
I did the CP/M port with a friend. It later turned out that
the Altos computer was near identical, just patching the
I/O addresses would have been enough.
Later I even got a 1MB RAM floppy, powered by 8086.
(really to do a paid CP/M-86 port  :-)
regards, Gerhard

Date Sujet#  Auteur
23 Apr 24 * Zilog stopping Z80 production31Jan Panteltje
23 Apr 24 +* Re: Zilog stopping Z80 production13Dan Purgert
23 Apr 24 i+- Re: Zilog stopping Z80 production1TTman
23 Apr 24 i`* Re: Zilog stopping Z80 production11Jan Panteltje
23 Apr 24 i `* Re: Zilog stopping Z80 production10Peter Heitzer
23 Apr 24 i  +- Re: Zilog stopping Z80 production1Don
23 Apr 24 i  +* Re: Zilog stopping Z80 production7Don Y
23 Apr 24 i  i`* Re: Zilog stopping Z80 production6boB
24 Apr 24 i  i `* Re: Zilog stopping Z80 production5Don Y
24 Apr 24 i  i  `* Re: Zilog stopping Z80 production4boB
25 Apr 24 i  i   `* Re: Zilog stopping Z80 production3Don Y
25 Apr 24 i  i    `* Re: Zilog stopping Z80 production2boB
25 Apr 24 i  i     `- Re: Zilog stopping Z80 production1Don Y
24 Apr 24 i  `- Re: Zilog stopping Z80 production1Jan Panteltje
24 Apr 24 `* Re: Zilog stopping Z80 production17Edward Rawde
24 Apr 24  `* Re: Zilog stopping Z80 production16Don Y
24 Apr 24   +* Re: Zilog stopping Z80 production10Lasse Langwadt
24 Apr 24   i+* Re: Zilog stopping Z80 production8boB
25 Apr 24   ii+* Re: Zilog stopping Z80 production6Lasse Langwadt
25 Apr 24   iii+- Re: Zilog stopping Z80 production1Don Y
25 Apr 24   iii`* Re: Zilog stopping Z80 production4Edward Rawde
25 Apr 24   iii `* Re: Zilog stopping Z80 production3Don Y
25 Apr 24   iii  `* Re: Zilog stopping Z80 production2Edward Rawde
25 Apr 24   iii   `- Re: Zilog stopping Z80 production1Don Y
25 Apr 24   ii`- Re: Zilog stopping Z80 production1Don Y
25 Apr 24   i`- Re: Zilog stopping Z80 production1Don Y
27 Apr 24   `* Re: Zilog stopping Z80 production5albert
27 Apr 24    +* Re: Zilog stopping Z80 production2Gerhard Hoffmann
27 Apr 24    i`- Re: Zilog stopping Z80 production1Jan Panteltje
27 Apr 24    `* Re: Zilog stopping Z80 production2Don Y
14 May 24     `- Re: Zilog stopping Z80 production1Don Y

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