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WTB: NEC V20 CPU - D70108H or D70108HCZ

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    WTB: NEC V20 CPU - D70108H or D70108HCZ

    I'm in need of a NEC V20 CPU, type D70108H / HCZ. This is the CMOS version of the chip. Please LMK if you have a spare. Thanks!
    Am Heimcomputer sitz' ich hier
    Und programmier' die Zukunft mir

    #2
    The V20 (D70108) has always been CMOS, as far as I know. At least that's why my databooks proclaim. It was Intel who stuck with NMOS/HMOS longer than the competition. So any V20 should do just fine, unless you have a need for a high clock speed rating. There are plenty on eBay.

    Comment


      #3
      Hes right. And i just bought a couple off ebay relatively cheap.

      Comment


        #4
        Not the cheapest but I bought 1 from this guy in December and have been using it almost daily since then.
        My fear with ebBay is always getting rebaged or completely fake parts as I did with my V30 later so I appreciate when someone gives a link to a 'known good' seller.

        https://www.ebay.com/itm/383373147908

        Comment


          #5
          You just need to hunt around. I bought from this guy and it was cheap https://www.ebay.com/itm/D70108D-8-I...qzty/282256007

          Comment


            #6
            That link gives a 404:

            We looked everywhere.
            Looks like this page is missing. If you still need help, visit our help pages.

            Comment


              #7
              Hey guys,

              I specifically need the 'H' version of the chip, it's for the V20-MBC project. Here's what the designer says about it:

              "An easy to build homemade single board computer with a V20HL aka uPD70108H (...) or 80C88"

              And in more detail..

              "Please remember that a CMOS full static CPU is required here, so the only V20 CPU that can be used is the V20HL (uPD7108H, see the “H” at the end of the part code that makes the difference…).
              Only this CMOS full static version allows to use a clock rate from DC and, under some conditions, guaranties that the logic levels are compatible with the Atmega32A ones (the Atmega logic input levels are not TTL compliant)"

              FYI - The design uses an Atmega32 as the IO subsystem, BIOS and as a replacement for the normally required glue logic ICs that populate most legacy designs.

              Here's a link to the project if you're interested: https://just-for-fun.org/v20-mbc



              Am Heimcomputer sitz' ich hier
              Und programmier' die Zukunft mir

              Comment


                #8
                Originally posted by VERAULT View Post
                You just need to hunt around. I bought from this guy and it was cheap https://www.ebay.com/itm/D70108D-8-I...qzty/282256007
                That eBay item is no longer in the system.
                ​​​​​​
                If I knew of a RELIABLE Chinese source for the chip, that would be fine. But really, I'd much prefer to buy a common, workaday example from someone's collection or spares shelf.

                Am Heimcomputer sitz' ich hier
                Und programmier' die Zukunft mir

                Comment


                  #9
                  Originally posted by WimWalther View Post

                  That eBay item is no longer in the system.
                  ​​​​​​
                  If I knew of a RELIABLE Chinese source for the chip, that would be fine. But really, I'd much prefer to buy a common, workaday example from someone's collection or spares shelf.
                  Yes it is, there are still two for sale and this link works for me: https://www.ebay.com/itm/D70108D-8-I...y/282256007671

                  Comment


                    #10
                    Originally posted by WimWalther View Post
                    Hey guys,

                    I specifically need the 'H' version of the chip, it's for the V20-MBC project. Here's what the designer says about it:

                    "An easy to build homemade single board computer with a V20HL aka uPD70108H (...) or 80C88"
                    Okay, got it "H" parts do allow operation down to DC. CH also. Most folks use the V20 as a drop-in for the 8088; it doesn't matter in that case.

                    There's a HK seller for one 16MHz HCZ[

                    Also one in California Here
                    Last edited by Chuck(G); April 17, 2021, 04:26 PM.

                    Comment


                      #11
                      Originally posted by VERAULT View Post

                      Yes it is, there are still two for sale and this link works for me: https://www.ebay.com/itm/D70108D-8-I...y/282256007671
                      Ok, now that link does work, and it's a nice, vintage part - but unfortunately, it's not the 'H' version, and as such not supported by my board.

                      Fyi, I do have a very similar part to the one pictured, and plan to try it out at some point. The project author indicates reports of success with one..
                      Am Heimcomputer sitz' ich hier
                      Und programmier' die Zukunft mir

                      Comment


                        #12
                        Originally posted by Chuck(G) View Post

                        Okay, got it "H" parts do allow operation down to DC. CH also. Most folks use the V20 as a drop-in for the 8088; it doesn't matter in that case.

                        Also one in California Here
                        ​​​​​​
                        Careful - I've come across that listing as well. The auction title indicates an 'H' series part, but the chip isn't so marked. It's marked as a regular D70108C.

                        I might contact him about the discrepancy.

                        Am Heimcomputer sitz' ich hier
                        Und programmier' die Zukunft mir

                        Comment


                          #13
                          Sometimes the sellers are just lazy and use photos that they already have on hand. I've definitely run into listings that say "the thing pictured isn't what you'll be getting.".

                          Comment


                            #14
                            Originally posted by Chuck(G) View Post
                            Sometimes the sellers are just lazy and use photos that they already have on hand. I've definitely run into listings that say "the thing pictured isn't what you'll be getting.".
                            I did message him, let's see what he has to say.

                            UPDATE: And here's what he said..

                            "HI

                            Sorry about that we have put wrong picture. But we will ship D70108HCZ-16, as we order against title description, not the picture.

                            Regards,

                            Raymond"

                            So there you have it, wrong photo. Thing is, you can never really tell in these cases - did they insert the wrong photo, or the wrong description? In any case, I always contact them first.
                            Last edited by WimWalther; April 18, 2021, 10:01 PM. Reason: Received seller reply
                            Am Heimcomputer sitz' ich hier
                            Und programmier' die Zukunft mir

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