Product requests

[MbeeTech]

Hi Ewan,

I have a few of ideas - they're probably wildly impractical, thought I'd mention them anyway.

1) Microbee mods, eg:
a) Bits with a switch you could solder in giving you a choice of Microbee versions.
    I think it would be interesting to switch my premium plus unit to a 16 or 32K system with the flick of a switch.
This would actually be reasonably easy to implement with a simple loader to put ROM basic in place in memory from the SDcard and jump to it.
I'll look into this for you.  No hardware mod needed.

b) When I had my first Microbee (a 32K I think) I remember being really interested in using the expansion port at the back of the 
machine - never did, and the premium plus doesn't seem to have this - but some sort of similar interface would be really interesting
Ernest has answered this (thanks Ernest), however, there is one sticky point in that the 50Way expansion connector on the 
Premium Baseboard in the Premium Plus is not actually vacant for population of the connector.
In the Premium Plus there is a 2 pin connection used at this location (within the 50way connector pinout) used to make
BUSREQn & BUSACKn signals available to the Premium Plus coreboard.   These signals are needed for 2 reasons :
1) For Floppy disk emulation to take place, Reads & Writes to the Floppy disk controller IO ports are sensed by the FPGA and certain
cycles are trapped for the coldfire processor to process.  While these functions are being processed, the Z80 processor needs to be 
stopped from processing any more instructions and BUSREQn / BUSACKn are used to take control of the Z80 buss for this reason.
2) So that the Coldfire can use the normal Microbee hardware (screen / PIO / Keyboard etc..) the Z80 needs to relinquish control.
The Coldfire processor can then read / write any area of memory or IO that the Z80 normally has access to.  This is used so that the
Coldfire processor can run its own software and have a user interface as in the Boot Manager Screen / Firmware update utility / uClinux.

If you wanted to add a 50 way expansion port to the baseboard, it is still possible, but you would have to find another method of ensuring
that the BUSREQn & BUSACKn signals are still connected to the coreboard from the baseboard.

>perhaps having the ability to connect the microbee to a Raspberry Pi too? 
You might have to expand on that to let me know what the purpose might be.
As Ernest said though, the Classic-Plus will have an Arduino like interface as an option with Digital and Analogue IO available.
Note that the Microbee takes the place of the Arduino in this case, rather than plugging an Arduino into the Microbee.
This is supposed to give the Microbee the same usable IO as the standard Arduino Uno board so that you can plug in 
Arduino expansion boards.

2) Floppy drive
Why not put a floppy drive kit together, complete with drive, instructions etc.
This would be great, however, no-one makes floppy drives any more.  The only second hand drives readily
available are 3.5" High Density drives and while these work, using a HD drive on Microbee Double Density disks
has it's drawbacks.  
Firstly, reading has no problem, and writing fresh disks also is o.k.
However, writing to disks previously formatted on a Double Density drive with a High Density drive is problematic.
The reason is that the track width (ie the width of the disk taken up by flux transitions per track) is typically wider by far 
on double density drives than on high density drives.  This means that if you write to a double density track with a high density
drive, the smaller flux width 'slices' the original data up (plows down the middle of it, so to speak).
When reading this fresh data back again, the read/write head sees not only the transitions of the flux from the required data
but also transitions that may exist between the edge of the old 'FAT' data track and the 'thinner' new track data.

3) Printer interface
I had a dot-matrix printer when I was kid - would love to again.
I know this one would be tricky given the availability (if any) of dot-matrix (or line-) printers around/being produced, but I really do miss that printer.
As Ernest mentioned, there are new printers that are available but they are expensive.  eBay is probably your friend here if you are looking out for a 
particular model.  If you are after one that is not necessarily a Microbee one, but will work I have a BMC-80 that I'd be happy to sell.
There may be an interesting project in a parallel port plug-in device that will convert dot matrix commands to postscript data for printing on a modern printer.   


4) FPGA recreation
I know this is probably way too huge... An FPGA based Microbee would be superb (much like the Spectrum Next or MEGA65).
You could do a kickstarter campaign, there looks to be a number of very skilled technical types on this forum that I'm sure would love to help! 
This is something I've been tossing around.  Most of the work will actually have been done with the work being done for the Classic-Plus / 256TC-Plus.
No need for a Kickstarter campaign on this one, save an except for the promotional aspect of it.
I've been looking at 2 alternatives (including a full FPGA Bee) because I know that a certain percentage of the Classic-Plus / 256TC-Plus customers will
want their machines built & tested.  I can't offer that for through-hole products as the assembly time is too great, so I've been looking at either
a full FPGA implementation, or a surface mount version of the Classic-Plus that would be much easier to run through our Pick & Place machine.

Thanks for your thoughts.  Appreciate the time you've taken to put them down.