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Can someone help me find the perfect Z80 for the propeller 1? — Parallax Forums

Can someone help me find the perfect Z80 for the propeller 1?

cbmeekscbmeeks Posts: 634
edited 2015-10-19 13:10 in Propeller 1
OK, I'm ready to finally plug a real Z80 into the breadboard and interface with my C3 board. I have a basic video driver going and I want to start executing code directly from the Z80 (much like the Mini80 project).

I'm more familiar with the 6502 line of CPU's so the Z80 is a little new to me.

Here is what I believe I need:

1) CMOS Z80 (so that I can control the clock) that can run from 3.5 - 4.0 MHz (more would be OK, but I *need* 3.5 MHz to work).

2) 3.3V would be awesome (still, at 3.5MHz)

3) Must be 100% backwards compatible to legacy Z80 code (such as ZX Spectrum, Colecovision, etc.)

As an added bonus, it would be nice to be able to get it in either DIP or surface mount.

I've looked on the Zilog site but I must be missing something. I've read that some of the newer Z80's (the super fast ones) aren't 100% backwards compatible.

Any suggestions on the model number and/or where to get them would be much appreciated.

Thanks!!

Comments

  • kwinnkwinn Posts: 8,697
    edited 2015-10-19 14:27
    Found these by searching for “Z80 dip”.


    http://uk.farnell.com/zilog/z84c0008peg/mcu-8bit-z80-8mhz-dip-40/dp/1081890

    http://www.digikey.com/catalog/en/partgroup/z80/15507

    Found this by searching for “Z80 dip 3.3V”

    http://ca.mouser.com/search/Refine.aspx?Keyword=ZiLOG+Z80+Microprocessors&No=25&FS=True

    Google is your friend. Many other results for each search.
  • TorTor Posts: 2,010
    edited 2015-10-20 01:59
    The 3.3V requirement is probably the difficult one. It's easy enough to find CMOS Z80 CPUs which are 100% compatible with the old ones but run from DC to up to 20MHz. They're called e.g. Z84C0020PEC for the 20MHz one and Z84C0008PEC for the 8MHz one, and so on. PEC are DIP versions. Very easy to find on Ebay, thus I have lots of them (hoarding syndrome..)
    But then there's that 3.3V issue.. if I'm not mistaken we had a thread here at the forum a year or so ago about mixing a Z80 with a Propeller (therefore Dr_Acula was certainly involved), where the voltage issue was discussed.
  • cbmeekscbmeeks Posts: 634
    @Tor, I believe you're right. I remember reading about that now.

    Yeah, I have several Z80's in DIP but I cannot tell from the markings (almost not even there) if they are CMOS or not. And, I just don't know enough about Z80 to know what I'm looking at.

    For example, can these 6-20MHz versions run at 3.5MHz?

    Thanks everyone.
  • blittledblittled Posts: 681
    The Z80 can run at any clock speed below the speed it is certified for so a 6Mhz chip should run ok with 3.5. I found one site which a person used an Arduino to clock a Z80 and pump NOPs at a low speed so he could analyze the signals on an oscilloscope.
  • Heater.Heater. Posts: 21,230
    Check out the N8VEM Z80 computer project. With Propeller for I/O:
    http://forums.parallax.com/discussion/115397/n8vem-propeller-propio

    A google for "N8VEM" and "propeller" will find you a ton of links.
  • cbmeekscbmeeks Posts: 634
    Awesome!

    Thanks for the info.
  • TorTor Posts: 2,010
    edited 2015-10-20 02:06
    cbmeeks wrote: »
    For example, can these 6-20MHz versions run at 3.5MHz?
    Yes, that's what I meant with 'DC to 20MHz' (for the 20MHz part). The core is static, just as for the 65C02, so there's no minimum frequency.
    For the CMOS parts, not the old NMOS parts. The CMOS versions are what have been in production the last few decades. Not sure exactly when they got introduced though. But the fastest NMOS part was 6MHz I believe, that was IIRC the one called 'Z80B'. In any case the CMOS parts have longer names.. all of the ones I find are called Z84C<lots of digits>.

    -Tor

  • yetiyeti Posts: 818
    From http://www.shaels.net/index.php/mini80/mini80-general/119-mini8o-overview ...
    One feature of the Mini80 is the ability to clock the Z80 CPU at any speed from 100 KHz up to 20 MHz with a max clock frequency error of 0.2%. I tested a number of 6 MHz, 8 MHz and 10 MHz Z80 CPU chips in the Mini80. The 6 and 8 MHz Z80 chips had a max stable speed of 3.6 and 5.1 MHz respectively very close to the estimated max clock speeds. The 10 MHz Z80 chips tested on the Mini80 all ran stable up to 10.2 MHz. I believe the most likely reason is that the parts are stamped 10 MHz but actually contain 16 MHz dies. A 16 MHz Z80 CPU should operate at 9.6 MHz max clock rate at 3.3 volts.
  • TorTor Posts: 2,010
    edited 2015-10-20 03:02
    Thanks for that link, yeti. I had seen it before but didn't remember where, or if my memory was correct.. about being able to run at 3.3 volts. I remembered the author's discussion about the 10MHz parts being different from the 8MHz (and lower) versions though, but I was fuzzy about the details.

    -Tor
  • cbmeekscbmeeks Posts: 634
    Thanks.

    Yeah, @Tor, I see that now. In fact, on Zilog's site under classic products, they have a couple of devices that say NMOS. So the "C" must mean CMOS. :-)

    It appears many of those products are Z80's with added features...or perhaps PIO devices?

    Anyway, I'm thinking the Z84C00 series is what I need. In DIP package, I believe it's:

    http://www.zilog.com/index.php?option=com_product&Itemid=26&task=parts&familyId=20&productId=Z84C00&mpn=Z84C0006PEG&mpnid=5565&scrollmpn=1&rootpage=b3B0aW9uPWNvbV9wcm9kdWN0JnRhc2s9cHJvZHVjdCZidXNpbmVzc0xpbmU9MSZpZD0xMzkmcGFyZW50X2lkPTEzOSZJdGVtaWQ9NTk=

    I might try ordering some of those soon.

  • Dr_AculaDr_Acula Posts: 5,484
    Z80+Propeller = fun!
    Those chips in the link above look like the right ones - standard cmos Z80 chips that have been around for decades.

    I look forward to seeing a design/schematic.

    Cheers, Drac
  • Heater.Heater. Posts: 21,230
    You know, after all that time messing with Z80 emulators and the odd real, old, Z80 chip, it never occurred to me to check. But you can still buy DIP Z80's new:
    http://www.digikey.com/product-search/en?pv16=12121&amp;FV=ffec7cc7,fff40027,fff80164&amp;k=zilog&amp;mnonly=0&amp;newproducts=0&amp;ColumnSort=0&amp;page=1&amp;quantity=0&amp;ptm=0&amp;fid=0&amp;pageSize=25

    http://media.digikey.com/photos/Zilog Photos/269-40-DIP.jpg

    At least the slow ones seem to be available.
  • TorTor Posts: 2,010
    edited 2015-10-21 07:33
    Yep, that's something the 65C02 and the Z80 have in common: They're still in production! Not many old-timers can claim that! 8080, 6809 (I wish that one was in production though), 6800, and others, all gone.

    BTW I figure the difference between the PEC and the PEG DIP Z80 versions is that the latter is RoHS while the former isn't - the PEC is easy to find on ebay, while on Digikey you'll only find PEG in stock.
  • blittledblittled Posts: 681
    I also would like to see details on this project. I've been wanting to interface a Propeller to the Z80 based ZX81. It would be similar to your project but with current limiting resistors on the buss so the Propeller could handle the 5V signals.
  • BeanBean Posts: 8,129
    blittled wrote: »
    I also would like to see details on this project. I've been wanting to interface a Propeller to the Z80 based ZX81. It would be similar to your project but with current limiting resistors on the buss so the Propeller could handle the 5V signals.

    I'd be interested in this too.

    Take a look at what is currently sitting in my basement...

    Bean
    Sinclair Setup.jpg
    2592 x 1456 - 864K
  • blittledblittled Posts: 681
    Awesome! Another Timex Sinclair user! I have 2 TS1000s, 1 ZX81, 1 Homebrew ZX80/81 called ZX-Core and a DE0-Nano running ZX-Gate which is a FPGA ZX81. There is a good forum sinclairzxworld.com and a good online shop sellmyretro.com.

    I plan on making a AY sound system, PS2 interface, WII Nun-Chuck interface and SD Card reader which uses a modified rom called ZX-PAND. Hopefully I can set up some sort of boot process that loads ZX-PAND from a SD card to a 8K SRAM with the internal ROM disabled. I think the Propeller is capable of doing all this. :)
  • Heater.Heater. Posts: 21,230
    So that's what a Timex Sinclair looks like. Cool! Not quite a jazzy as the real thing but cool.
  • BeanBean Posts: 8,129
    Yeah, I'm a giant Timex Sinclair fan. It was my 1st computer. I logged many (many) hours at a TS1000 in my youth.

    Heater, In the picture is a Timex Sinclair 1500 (not a Timex Sinclair 1000).

    The 1500 had the 16K RAM built-in, and also had a better keyboard (same keyboard as the ZX Spectrum).

    I have a couple 1000's around, but the 1500 is so much nicer to type on. Plus you can plug in the 16K RAM pack and get 32K of RAM on the 1500 (Plugging in the RAM pack moves the 1500's internal 16K up to the 32-48K region).

    I would like to use a Propeller to emulate the 16K RAM, and provide a VGA output of the screen text (you can tell when the TS1000 is accessing video memory because it "appears" to be executing code above 32K). So the VGA output should be possible.

    Bean
  • cbmeekscbmeeks Posts: 634
    That's an awesome computer, Bean. I have a TS1000 and a ZX81. I just recently got a 16K ZX Spectrum that I am restoring.

    All together, I have about 60 "retro" computers. Everything from C64's, Atari's, etc. Even a Mattel Aquarius in mint condition. lol

    Anyway, my goal is build a ZX Spectrum clone. I figure that is about as simple as it gets when it comes to vintage computers. Well, vintage computers that have a ton of software available.

    My problem is that I am an amateur engineer at best. So it will be a while before I get anything usable.
  • David BetzDavid Betz Posts: 14,516
    cbmeeks wrote: »
    That's an awesome computer, Bean. I have a TS1000 and a ZX81. I just recently got a 16K ZX Spectrum that I am restoring.

    All together, I have about 60 "retro" computers. Everything from C64's, Atari's, etc. Even a Mattel Aquarius in mint condition. lol

    Anyway, my goal is build a ZX Spectrum clone. I figure that is about as simple as it gets when it comes to vintage computers. Well, vintage computers that have a ton of software available.

    My problem is that I am an amateur engineer at best. So it will be a while before I get anything usable.
    I don't suppose you live near NH and want an Atari 800xl? I'm trying to get rid of old machines that I will probably never use.

  • cbmeekscbmeeks Posts: 634

    David Betz wrote: »
    I don't suppose you live near NH and want an Atari 800xl? I'm trying to get rid of old machines that I will probably never use.

    No I live in Hixson, TN but would love to have it. :-)

    Could I send you postage via PayPal?

  • David BetzDavid Betz Posts: 14,516
    edited 2015-10-22 16:53
    cbmeeks wrote: »
    David Betz wrote: »
    I don't suppose you live near NH and want an Atari 800xl? I'm trying to get rid of old machines that I will probably never use.

    No I live in Hixson, TN but would love to have it. :-)

    Could I send you postage via PayPal?
    Probably. I need to find a box for shipping though.
  • cbmeekscbmeeks Posts: 634
    Email sent.

    Thanks again!
  • cbmeekscbmeeks Posts: 634
    BTW, I just got 3 of the Z80's shipped to me for free. :-D

    Zilog has a sample program. While they didn't have the one I wanted, I did get three of the:

    Z84C0020VEG IC MPU Z80 20MHZ 44PLCC

    PLCC so that's going to suck. LOL. But hey...maybe I can make a cheap breakout board?

  • Dr_AculaDr_Acula Posts: 5,484
    PLCC so that's going to suck. LOL. But hey...maybe I can make a cheap breakout board?

    90c for a PCLL socket with 0.1" spacing on the pins http://futurlec.com/SockPLCC.shtml

    Or an adapter http://futurlec.com/PLCC_Adapters.shtml

    Probably available on ebay as well.
  • cbmeekscbmeeks Posts: 634
    Awesome! Thanks Dr_Acula.

    I might buy me ONE, TWO, THREE, FOUR of them. FOUR...AH AH AH!!!

    lol...sorry, I love the Count.

  • blittledblittled Posts: 681
    Time for me to blow the dust off my stash of old 4MHz Z80s and support chips :)
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