6502 or Z80… why should I choose? Can’t I simply have both? Sure, you can! Plug a Z80 card into your Apple //, boot with a CP/M floppy, and you are in. Drop the CAT for a DIR. It is that simple. Before looking at how can two microprocessors different as the MOS 6502 and the Zilog Z80 can coexist in the same computer (designer around the 6502), let’s answer the question: but why? Well, by allowing Digital research’s CP/M drive your Apple, you could immediately access to hundreds of professional applications. Among these additional applications, we can find many development tools such as Pascal or FORTRAN. But wait, there is another whoa effect here: because many of the languages were developed by Microsoft, under Paul Allen’s impulsion, MS developed and sold its own Z80 CP/M cards. In fact, they were the first out the door and were so successful that the product’s brand became a common name: SoftCards (check out my post about this product). Sure, over the years, several manufacturers proposed their own Z80 cards.
Applied Engineering, that I presented in my last week’s post was one of them. AE sold the Z-80 and Z-80 PLUS models. The latter is the one I keep in my Apple //e because it recognizes other AE productions such as the memory expansion cards. With a Z-80 card installed in the computer, the Apple behaves as an Apple (using the 6502) until you boot on a CP/M floppy. It is during the boot that the Z-80 card disconnects the 6502 from the address and data buses to takes control of the computer. Note that the 6502 always handles the interrupts, and the Z-80, when active, also handles the interrupts but performs the required memory address translations to allow the smooth cohabitation. Nevertheless, the assembly programmer had to perform many of these translations by hand. These were definitively different times :). Because the Z-80 can run Intel 8080 code adding a Z-80 card to your Apple // really opens-up your horizons.
Photography#Background#remove#for https://goo.gl/wW8Sjh
Photography#Background#remove#for https://goo.gl/wW8Sjh
In my younger days had never tried Z80 or touch an Apple.I was working at Intel and a “fierce” fanatic after all, and anything that we toyed around were based around Intels and a bit a on Motorola 68xxx since they are only next door.Ha, ha, ha!
Am aware that Z80 used to have a cult following in those days.
https://plus.google.com/photos/…
In my younger days had never tried Z80 or touch an Apple.I was working at Intel and a “fierce” fanatic after all, and anything that we toyed around were based around Intels and a bit a on Motorola 68xxx since they are only next door.Ha, ha, ha!
Am aware that Z80 used to have a cult following in those days.
https://plus.google.com/photos/…
Kakistocracy indeed, Z-80 was a huge success – and still is nowadays! And we still can source it easily. In the sort, with your Intel preference & background, you could be a honorific member of the Z-80 club. After all, the chip was designed by Frederico Faggin, a former Intel employee. Small world 😉
Kakistocracy indeed, Z-80 was a huge success – and still is nowadays! And we still can source it easily. In the sort, with your Intel preference & background, you could be a honorific member of the Z-80 club. After all, the chip was designed by Frederico Faggin, a former Intel employee. Small world 😉
Jamel Tayeb Still alive and kicking the Z-80? I’ll be damn.
Jamel Tayeb Still alive and kicking the Z-80? I’ll be damn.
Kakistocracy yes it does, and is part of many designs (SoC) from the maker. zilog.com – http://www.zilog.com/force_download.php?filepath=YUhSMGNEb3ZMM2QzZHk1NmFXeHZaeTVqYjIwdlpHOWpjeTlWVFRBd056Y3VjR1Jt
Kakistocracy yes it does, and is part of many designs (SoC) from the maker. zilog.com – http://www.zilog.com/force_download.php?filepath=YUhSMGNEb3ZMM2QzZHk1NmFXeHZaeTVqYjIwdlpHOWpjeTlWVFRBd056Y3VjR1Jt