Classic Plus Development Updates

[Mr Lurch]

Awesome to hear an update. Super, super excited to get my filthy little hands on one.

[IanMcLean]

It's good to get another update. I am also really excited about the new machines Ewan! :-)

[MbeeTech]

Thanks for the encouragement guys.

Mr Lurch - good to see you here too. Hope you are doing well.

Chesh - The Dragonball is actually a part on the board rather than a softcore within the FPGA. I was initially trying to use a MC68000 compatible core within the FPGA, but I wasn't happy with the
performance, and more than that, it made it more complicated for the [FPGA] logic design to pass [meet] timing constraints - the 2 problems actually go hand in hand.
I initially looked at putting a coldfire processor on it (like on the Premium Plus coreboard), but the instruction set (even though it came out of the M68K set) is not compatible, so software is not as easy to
come by, so an M68k Softcore or the Dragonball Super VZ (physical part) processors were the options I went with. CP/M 68K shouldn't be hard to get going on it, and there are some other OS's that I'll
be investigating as well.

[MbeeTech]

Another little update :

It now boots from the SDcard.
The Floppy emulation firmware is all run on the Dragonball processor with registers and interrupt logic in the FPGA to assist.
There is a fair bit of optimization to do still, but another tick on the todo list :-)

[CheshireNoir]

Awesome! And thanks for the insight into the design. I do love gleaning why people make the choices they do make.
Cheers!

John

[MbeeTech]

The next steps in the development cycle are all about Video and Sound outputs.

My intention is to do away with the old composite and RGB video outputs (Gasp!).
It's getting tricky these days to find suitable monitors / video output solutions to see
a Microbee's output with good quality.  While there are still plenty of TV's around that
will accept the standard monochrome composite video output from the bee,
colour output usually means finding an upscaler or a device with a Scart input and 
making up suitable cables / interface circuitry.  
I just don't want people to have to buy something else to get a decent picture out of 
their new kit.

Proper HDMI output is now what I've decided to implement.  It makes it simple to get
decent quality video out, and no problem with finding a suitable display to run it on.

   

I've designed a small development board [above] for the parts I want to use that will go onto 
the FPGA board in place of the RGB output section.  The PCB has been ordered today.
If you have a look at the board, it also has an I2S DAC for the sound and line level stereo output.
The I2S bus also connects to the HDMI transmitter, so you will be able to have sound output
from your chosen display as well (assuming it has speakers) via the HDMI cable.

I'll be upscaling the Microbee's video within the FPGA to either 640 x 480 or 1280 x 960.
I will wait and see the results of the upscaling on both resolutions before committing to one.

As well as supporting the Microbee's normal bit bashed (via the PIO) sound, I'll be implementing 
8 bit dual channel (stereo) sound FIFO's.  The bit bashed sound will be summed into the stereo 
audio as well.

I'm very much looking forward to getting these 2 important parts implemented.

Stay tuned.

[greg221b]

Hi Ewan,

I'm guessing the new Microbee will be caseless still? I saw an interesting RetroRecipes youtube (https://www.youtube.com/watch?v=DnucTE4bYi4) where he gets a C64 case 3D printed by PCBWay.

Without much research, I have the impression there's software that will generate a 3D model given stacks of photos from different angles.

I was wondering if you (or anyone else reading) has thought about creating a 3D model of the Microbee case and having it printed by a company like PCBWay?

I'd be happy to take pics/work out 3d modelling software/print smaller chunks with my Ender 3 Max Neo. You'll have the rights to the model.

Greg

[MbeeTech]

Hi Greg.

There are 2 models coming out - the one without the case, and one in the 256TC case.
They are essentially the same machine, but the one without the case keeps the cost down
and the one with the case and new keyboard is the full product and the form factor going forward.

I've had many discussions over time regarding redoing the original (Premium) case set, and the upshot is that
to do it properly involves getting new injection molds made (3 of them) which is a very costly process - whereby
the volume [of sales] required to recover costs is just too great.
I realize that it is the traditional Microbee shape, and that is somewhat important for the retro market, but still
it is not something that will be done.
Moreover, the new models have a lot more to them than traditional bees, so it's a good time also to draw a line in the
sand and move forward.
Having said that, David Vermont (Vivvid) has been recreating Premium Case set for 3D printing from the original drawings
and optimising it for 3d Printing process.  I'm not adverse to people 3D printing their own, if they so desire, as long as
it's for their personal use.
I would say to people considering a 3D printed case - just go ahead and buy the fully cased machine - you will love the
new (larger) keyboard and form factor if you give it a go.


   

[CheshireNoir]

Look forward to the 256TC style case. I've got plenty of the classics (Plus the one currently housed in lasercut MDF. Maybe this weekend I'll finally finish off the clear acrylic version of that case?)

John

[MbeeTech]

 Maybe this weekend I'll finally finish off the clear acrylic version of that case?

John

I really like the sound of that John.  Would be great option for the 'uncased' new kit as well.
Perhaps we can investigate this and get you something for your efforts, while making it available
as a product?