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Powertran Cortex

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    Originally posted by Stuart View Post
    If you're rebuilding the code, what do you make of this? VDPDSR module, page 10, last line in the 'TEXT MODE' block - JHE FTMODE. Shouldn't that be a JL REMCUR jump (to the following block) followed by a BLWP @FTMODE since FTMODE comprises a WP pointer and PC pointer? [I'm working on porting the code across to my TM990 9900-based system so have been looking quite closely at it.]


    (tms9995 - also sent you a PM)

    Don't see a PM...

    The code in the pdf listing is what's running in the Cortex. I'm not sure what you point out is right or wrong without looking at it in detail although, if it was a JL REMCUR, it would be pointless as the next instruction executed would be the one located at REMCUR whether it made the jump or not. The sources I have reconstructed are based on some files I found on an old disk a while back. They were not up to date and I had to create some from scratch! I modified them to match the PDF. After assembling each module, I then do a binary compare of the linker output with an image of the original ROM to confirm the source produces the correct code.

    I also have recovered a bunch of MDEX disk images. These include QBASIC, SPL, Pascal and Forth compilers and also the full-screen text editor Window. I will put all this together with the latest emulator when I can.

    I plan on producing a couple of utilities that provide for disk formatting and disk image creation on the Cortex. These would be down-loaded from a PC to the Cortex via RS232 comms.

    I'm doing my best...


      Originally posted by nige the hippy View Post
      I'm running seriously short on space but..... Wasn't that the original Autocad machine? If Ksarul can't take it, and you're not TOO far away, and you want it gone, then can you put me on the list please!
      Check out the history of Autocad on John Walker's site:

      Do a search for M9900, QBASIC, MDEX, Marinichip etc.


        [QUOTE=Stuart;160491] [I'm working on porting the code across to my TM990 9900-based system so have been looking quite closely at it.]

        TM990? If this is T-bus stuff, there's probably a collection of T-bus boards and 99xx chips at Hill Lane. We even built a few 99000 boards at one time.



          Originally posted by Stuart View Post
          [I'm working on porting the code across to my TM990 9900-based system so have been looking quite closely at it.]

          TM990? If this is T-bus stuff, there's probably a collection of T-bus boards and 99xx chips at Hill Lane. We even built a few 99000 boards at one time.

          Yes, its the T-bus stuff. Can I just come over and rummage through all your cupboards?

          If you sort out what you're happy to get rid of, I'm more than happy to come and collect.



            As I finally got a chance to drop in here after a long forced absence--I am definitely interested in the Marinchip machine, as I've been looking for one of those for a long time! Didn't MPE also make the hard disk interface for the Cortex? One of those would be a very interesting find as well.
            Enter My Mind At Your Own Risk!


              In the VDP section of the Cortex circuit diagram + technical description document, there are two graphic screenshots which I assume were drawn in BASIC using the Cortex. Does anyone by chance have the BASIC listing to produce these? (They're not in the Cortex user guide - I've looked there already!)



                Unfortunately, I don't have the BASIC listings, Stuart. I have almost finished doing a complete restoration of the 74LS2001 manual though. I have two small diagrams to recreate and then I will upload it to WHTech--with luck, this weekend. The copy I had was missing a small bit at the end of each line on a lot of pages, but I was able to deduce the correct text for all but two lines--not bad for a 24-page manual, especially since both of them were in the chip's introductory blurb, so the meat of the document is complete.
                Enter My Mind At Your Own Risk!


                  Undocumented Basic Command

                  Going through the Basic source code I've come across an undocumented Basic command - SWAP - which does a screen colour substitution in GRAPH mode.

                  To use it, first there is a bug in one of the jumps in the code that needs to be corrected:

                  MWD(3390H)=1308H (the original value should be >13EF)

                  You then need to set up the colour substitution table. This is stored in the 16 bytes from >00A4 to >00B3. Initially these contain the values >00 to >0F. What the command does is go through the screen colour table and if a pixel currently has the colour code 0 then it replaces that with the colour specified by the colour code in the first byte of the table. If the current colour code is 1 then it replaces that with the colour specified by the colour code in the second byte of the table, and so on. The colour codes are as specified on page 4-77 of the user guide.

                  So as an example, the following should work:

                  10 MWD(3390H)=1308H (correct the bug in the code)
                  20 MEM(00A8H)=2 (change everything thats dark blue to medium green)
                  30 MEM(00ABH)=6 (change everything thats cyan to dark red)
                  40 GRAPH (graph mode, default is dark blue text on cyan)
                  50 PRINT "HELLO WORLD" (print some text)
                  60 WAIT 100 (delay 1 second)
                  70 SWAP (swap colours in screen colour table)


                    Originally posted by Ksarul View Post
                    Anyone else on the forum have a Cortex? I just got one and I don't have a lot of information on it yet..

                    I used to have one I built in the early 80s. Unfortunately after many years of it sitting in my damp garage it got so rusted I ended up throwing it away

                    It was a superb machine for its day, sadly not a lot of software for it. A situation I find myself in now with my Amiga systems.

                    If any of you have the game CBlocks, a tetris clone for the Cortex, it was me that wrote it BTW !

                    I do still somewhere have all my manuals, plus designs for an Eprom programmer I made for the E-bus.

                    Going to using hard drive based machines seemed a bit of a backward step after I was used to everything being loaded in from Eproms on my Cortex.

                    Great to here there are people still using the Cortex and actually have heard of them. When I searched the net a few years ago no links came up for Powertran Cortex.

                    Brings back memories, the Cortex was my pride and joy for many years.


                    PS. I should also have all the Cortex User Group newsletters still around somewhere.
                    Last edited by BillEaves; March 11, 2011, 04:18 AM. Reason: Added info


                      Hi Bill,

                      Welcome to our Cortex Forum!

                      Glad we could stir up some fond memories. Anything you can add to our documentation collection would be greatly appreciated. We are missing one or two Newsletters, so please take a look at the Whtech FTP site and see if you have the missing ones (or anything else you have and we don't!).



                        Just seen on EBAY.....


                        set of PCBs.

                        Please, somebody else buy them!
                        "Don't it always seem to go
                        That you don't know what you’ve got ‘til it’s gone" (BANG )


                          I've put on a massive bid of ... £1.00 ... so at least it won't end up unsold and in a skip.


                            Well done! I would have had to have done the same myself.
                            "Don't it always seem to go
                            That you don't know what you’ve got ‘til it’s gone" (BANG )


                              Way to go Stuart, you big spender. I put it on my Watch List


                                I'm actually going to be away next week without Internet access, so I'm going to have to contain my excitement for almost a week as to whether my £1.00 was the winning bid.

                                EDIT: Excitement over, I've been outbid. Which I'm sort of pleased about because getting all the bits together to build the boards up would be no small job. I feel I've suddenly got a couple of weeks of my life back.
                                Last edited by Stuart; August 11, 2011, 02:09 PM.