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Powertran Cortex

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    ETI tended to put the pcb layouts at the end of the magazine for people who made there own pcb's.
    So it may not have been scanned in with the article.
    Worth a look, i can look tonight.

    Jim

    Comment


      E-Bus connector.

      Anybody know what connector is fitted for the E-Bus on the motherboard.
      I thought it should be female (i.e no pins) but the pin labeling on the pcb (rows A and C) only matchs up with a male connector.

      Theres no hole for it in the Cortex 2 case so was it connected to expansion boards with ribbon cable ?

      Thanks,

      Jim

      Comment


        Originally posted by Jim Hearne View Post
        Anybody know what connector is fitted for the E-Bus on the motherboard.
        I thought it should be female (i.e no pins) but the pin labeling on the pcb (rows A and C) only matchs up with a male connector.

        Theres no hole for it in the Cortex 2 case so was it connected to expansion boards with ribbon cable ?

        Thanks,

        Jim
        Looking at the E-Bus motherboards on ...

        <http://quarndon.co.uk/index.php?main_page=index&cPath=54_55>

        ... they have female connectors (as far as I can see), so the boards would be male, so the Cortex should also be female?

        Have you got signal/pinouts for the E-Bus so you can check the signal connections against the pins? Give me a shout if not and I'll scan a copy.

        Stuart.

        Comment


          Hi Stuart,
          I had that thought as well and looked there.
          But, i'm sure i read somewhere that the Cortex looks like another card not a motherboard so that would make it male like the cards.
          The parallel port ETI article mentions the connector beinh male on the cortex but in electronics i quite often find that male and female get mixed up depending on what the person describing it decides is the male or female part of the connector.
          The pins or the housing.
          The pc legend for connector rows A and C and pins 1 and 32 matches up with a male connector i have but then the male connector numbering doesn't match up with a female connector when plugged into it !!!

          Many thanks,
          I have all the ETI articles and the 74LS2001 datasheet and patent.
          I don't think i have an actual pinout of the E-bus other than whats in the Crotex data.

          Many thanks,

          Jim

          Comment


            E-Bus spec:

            <www.avjd51.dsl.pipex.com/tm990/E-Bus_Spec.jpg>

            Feel free to take a copy.

            Stuart.

            Comment


              74LS2001 replacement.

              Hi All,
              Would anybody be interested in a plug in 74LS2001 replacement.
              I've done a PCB (14mm x 28mm) for one based on the 1985 ETI article but using surface mount 74LS04 and 74LS74 IC's.
              But the cheapest i can get the PCB made is 96 for any quanity up to 40 off.
              Anybody interested in a assembled module for say 15 +P&P (or less if if more than 10 people are interested but i doubt that !) to help spread the cost.

              Thanks,

              Jim

              Comment


                Originally posted by Stuart View Post
                E-Bus spec:

                <www.avjd51.dsl.pipex.com/tm990/E-Bus_Spec.jpg>

                Feel free to take a copy.



                Stuart.
                Thanks Stuart.

                Jim

                Comment


                  I've been working on a new layout for the parallel card from the same 1985 article, which will provide utility for the E-Bus as well if I can get some of the bare boards made up.
                  Enter My Mind At Your Own Risk!

                  Comment


                    Today is the day.

                    In a couple of hours (lunchtime) i should be put in the final few chips (Ram) and powering the first newly built Cortex for quite some time.
                    I already had it powered yesterday, firstly without any IC's fitted to check current drain and then with all the basic chips fitted except for the ram.
                    There was some activity on the busses but i didn't expect much without the Ram fitted.
                    If that works i have all the chips to fully populate the board except the 74LS2001 replacement.
                    Still trying to get the pcb for that made, i had sneaked it onto a spare part of a PCB panel for a new product here at work but it's not gone into production yet

                    Jim

                    Comment


                      It lives !!
                      Well, as far as displaying the Basic prompt on an old TV
                      I did try to take a picture of the TV but the camera wasn't very happy with that idea.
                      Couldn't do much else as i've not finished the keyboard yet.
                      Heres the board on my desk, excuse the mess !

                      cortex powered.jpg

                      Jim

                      Comment


                        Looks good Jim!

                        Comment


                          Excellent! I just got some keyswitches in today, so I should be able to assemble a keyboard soon--of course, the key caps weren't with the switches, so I hay have to do some creative surgery on some of the other keyboards I have to get what I need. . .on the 74LS2001 replacement board, I can do a quick add of it to the ExpressPCB file for the Parallel board--then you have both the access to the E-Bus and a card to use on it too. . .assuming I got all of the details right on the board.
                          Enter My Mind At Your Own Risk!

                          Comment


                            I know of one other individual trying to assemble a pair of cortices, so yours, mine, and theirs will add at least 5 to the known survivor list, Jim. Before we know it, we'll know where more than 20 cortices reside, though yours is only the second in a Cortex II case!
                            Enter My Mind At Your Own Risk!

                            Comment


                              Hi Ksarul,
                              I should still be able to get the 74LS2001 board done as part of our productioon boards for work and if it fits into a spare space on the panel it won't cost me anything.
                              Luckily a current project has a set of funny shaped boards so there is a gap.
                              But it may be a few weeks or a month before these boards get made.
                              Unfortunatly we use avery obscure pcb package called Boardmaker which has no export options at all apart from Gerbers.
                              I can send you a copy of the gerbers for my board if you wanted to add it to your parallel board.
                              I've attached a screen shot of the board, i still need to double check it against the schematic, especially with the mistake in ETI.

                              To be honest i may well not use the Cortex 2 case, i much prefered the original case with the built in space for the floppy drives.
                              I'm actually probably going to fit it into a old XT PC case and use the PC power supply as well.
                              The keyboard can either be in a modified pc keyboard case or i'll use a PC keyboard with a PIC based interface doing PS2 to parallel keyboard interface conversion.

                              Jim

                              74LS2001.jpg

                              Comment


                                Just noticed the picture hasn't got the ground plane turned on, it just covers the complete lower layer of the PCB apart from the one short track.
                                A header will be soldered onto the bottom of the board with the legs then cut off flush on the top side, then the SM ic's will be soldered on the top side.
                                I wanted to keep it as small as possible.

                                Jim

                                Comment

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