Memofest 2017 Photos

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1024MAK
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Memofest 2017 Photos

Postby 1024MAK » 15 Oct 2017, 15:25

The CFX II+ latest development:

IMG_5412.JPG
Memotech MTX with a CFX II+ running a colour display, plus a mono monitor showing the normal MTX output.
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IMG_5411.JPG
The screen output of the CFX II+
IMG_5411.JPG (559.21 KiB) Viewed 1076 times

IMG_5414.JPG
Close up of the CFX II+ circuit board
IMG_5414.JPG (531.88 KiB) Viewed 1076 times


Thanks of course to Bill, Dave and Martin for some great work with this 8-)

Mark
Last edited by 1024MAK on 16 Oct 2017, 20:34, edited 3 times in total.

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1024MAK
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Re: Memofest 2017 Photos

Postby 1024MAK » 15 Oct 2017, 15:30

IMG_5415.JPG
Hex-Train, the MTX Plus+ version was demonstrated
IMG_5415.JPG (620.43 KiB) Viewed 1075 times

IMG_5416.JPG
It's running on this MTX Plus+ system
IMG_5416.JPG (887.08 KiB) Viewed 1075 times


Hex-Train+, yet more wonderful work from Andy 8-)

Mark

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1024MAK
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Re: Memofest 2017 Photos

Postby 1024MAK » 15 Oct 2017, 15:42

IMG_5420.JPG
The magic of FPGA... REMEMOTECH
IMG_5420.JPG (710.64 KiB) Viewed 1072 times

(See Andy's site for more details...)

IMG_5419.JPG
What's this, another cake? I'll let Martin explain...!
IMG_5419.JPG (700.09 KiB) Viewed 1072 times

IMG_5418.JPG
And of course, the real cake...!
IMG_5418.JPG (595.94 KiB) Viewed 1072 times


More, you want more? And I don't just mean the cake (one of three cakes, mind! Yum!).
Well Andy's event report is here ;) Better yet, come to the next Memofest ;)

Mark

Martin A
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Re: Memofest 2017 Photos

Postby Martin A » 15 Oct 2017, 17:49

So last thing Sat, after everyone else had gone, Mark and I had a look at Paul D's MTX to try and work out why it was having video issues. By the time Mark had to leave for the long drive we still hadn't duplicated the fault, even with the extra load on the PSU of driving a CFX-II on the expansion connector.

Still I was able to get a shot of the MTX driving 3 separate screens
Three screens.jpg
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Sunday morning before Paul was due I had a further play with the board before Paul arrived to collect it on his way home.

It looked like one of the capacitors on the Video Daughterboard could possibly be shorting to a via on motherboard. Once small piece of insulating tape later the potential short was history. An hour long soak test and still no problems so hopefully that's one system fixed at least for now.

The 2nd repair booked for Sunday Morning was Jim with his red MTX. Which had no display.

We connecter it up to the monitor, and as expected the display was blank. However in order to know whether we had a black screen which is a common fault, or a blue one we connected the old TV. Which produced a flashing cursor and "Seady" and a few random exclamation marks on an otherwise working display. We swapped the daughter board and then on the next re-boot had the same display on both screens.

An close examination of Jim's daughter board provided the answer. The was no link in either of the 2 jumpers that allow colour or mono composite output. Fitting one link solved the missing display problem.

I plugged in the CFX-II board so that the start-up screen would give us a display to help diagnose the corruption of "Ready" into "Seady" and it was obvious that the lowest bit of the display ram wasn't outputting correctly. The Circuit diagram suggested this should be the chip in location G4 which we confirmed with a 10R resistor grounding Pin 14. That chip came out and was replaces with a socket and one of the re-cycled 4116 chips from the spares box. Video corruption solved.
Red MTX Board fixes.jpg
Red MTX Board fixes.jpg (1009.02 KiB) Viewed 1065 times

Martin A
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Re: Memofest 2017 Photos

Postby Martin A » 15 Oct 2017, 18:02

Next up was fitting the Magrom internally and a "test" of some of the games.

That revealed a 3rd problem the "H" key didn't work. Changing the cable didn't change anything so we connected my keyboard, that worked as expected, confirming the motherboard was fine and that the issue was the keyboard itself. Experimentation confirmed it wasn't just the "H" key, but also "F" Cursor right and a few others. All keys connected to the same pin on the keyboard connector. Tracing with the meter confirmed a break in between the connector and the first of the keys connected to it.

Being a Memotech, that required a yellow wire to restore connection.
Red MTX Keyboard Fix.jpg
Red MTX Keyboard Fix.jpg (637.72 KiB) Viewed 1065 times

With (hopefully) everything now fixed we were able to test the Magrom and confirm for now at least the Ultra Rare RED MTX WoW!! is working. Anf JIm was finally able to head for home with his repaired MTX and A large chunk of the Pothole Pete themed cake as souvenirs of his trip to the South Coast.
Red MTX under test.jpg
Red MTX under test.jpg (981.29 KiB) Viewed 1065 times

Martin A
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Re: Memofest 2017 Photos

Postby Martin A » 15 Oct 2017, 18:23

Mark poster a picture of a home made keyboard with a suggestion it might have been a cake. Of course it's not, Pothole Pete was the real cake.

The home made box hides a component reduces sort of MTX like system, one of a couple of experiments I'd tried with the intention of making a replacement Main board using more modern components.

MTX Mini.jpg
MTX Mini.jpg (550.3 KiB) Viewed 1065 times

Under the cover is a Z80 running at 9.8304 Mhz (the odd speed is a consequence of the requirements of the serial connection), memory, CTC, SIO and serial to USB adaptor, plus the various support chips. On the other side of the connector is a propeller video display from the CFX built onto a MTXplus compatible connector.

In theory it could run MTX basic, however it would need the display handler re-written. With only the 80 column display it's really intended to run CPM. Which it will, using the same disc images as the CFX and CFX-II, booted from a modified CPM rom.

Over all though it's still too big to fit the mounting rails under the keyboard in a real MTX. More work needed!

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JonB
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Re: Memofest 2017 Photos

Postby JonB » 15 Oct 2017, 18:59

Sorry, just got to say again.. that red MTX is the sexiest 8 bit machine full stop. I could sit and stare at it all day. No, really!

Martin A
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Re: Memofest 2017 Photos

Postby Martin A » 15 Oct 2017, 19:48

JonB wrote:Sorry, just got to say again.. that red MTX is the sexiest 8 bit machine full stop. I could sit and stare at it all day. No, really!

Jim can sit and play games on it all day now hopefully!

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Crazyboss
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Re: Memofest 2017 Photos

Postby Crazyboss » 15 Oct 2017, 20:13

seems like a few mtx's was fixed too :) cool

Thanks guys for another great event, hope to join it next year, if some one want to host it....
//CLAUS - Webmaster at www.mtxworld.dk

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Dave
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Re: Memofest 2017 Photos

Postby Dave » 16 Oct 2017, 17:57

1024MAK wrote:The CFX II+ latest development:

Thanks of course to Martin and Bill for some great work with this 8-)

Mark


No mention for me then :-(


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