Offtopic:

I just opened as new website about solid state drive s, or: ssd's.
The site will be filled with a list of all ssd's on the market, including their specs, but will also contain lot's of links to reviews, benchmarks and price lists.

Click here to visit www.SsdWorld.Net!

If you like it or not: I'm going to create a new website that will be dedicated to everything that's happening around the MB02.

There's such a lot of information on the web, but mostly on the most exotic places or corners of websites, that I believe it's very nice to have a collection site with links to all of them and have information about all the developments going on at the moment.

It will not be a copy of sites, forums etc, but more a start place to be able to connect information on different site together.

Also I have received hundreds of emails in the past about the MB02, with info I'm sure of is nowhere on the web.

So, start clicking to:

The new MB02 website

After some discussing with Ingo, Miguel and others I did some modifications on the PC keyboard interface.
Here's the result:


Another way of handling /IORQ
The resistor R1 is removed which used /IORQ on a 'dirty' way to enable the 541.
A second BC337 transistor is added with it's base connected to the /IORQ signal (left pin of the removed R1), with collector and emitter connected to the collector and emitter of the other BC337 already present.
Then a pull-down resistor is added to emitter of both transistors.

Lowering the load on D0..D5
Also 5 smd resistors are added to the outputs of the 541, so the interface does not do a high load; I saw this was also done on the Kempston Mouse Turbo. Don't know if it will ever make a difference.

I must have the new logic described in words somewhere, but hey, it works ;)

By the way, I'm not ready experimenting with the MB02 + PCKI compatibility problem yet.
It seems the PCKI is not the main cause, but the distance between Spectrum and MB02 causes a lot of problems.
Especially with the 128K heatsink model which has a very poor clock signal, according to Ingo.

As I still have major problems getting the MB02 setup stable when a PC keyboard interface and/or Kempston Mouse Turbo is attached also, I decided for now to use a DivIDE inside the plexiglass case.

The 'reset'-button is now used as NMI switch, as it was supposed with the MB02+IDE, and the set works like a treat!

I connected the Compact Flash card on top of the case, where there is a hole for a casefan, so I can update the CF card without opening the case.

Here's a picture:

Here's a video showing how to convert any video into a format your Spectrum can handle.
The resulting format at the moment is a TAP-file filled with screen$-files.

Of course a mass-storage interface, such as DivIDE is required, for example the TAP-file that shows the video underneath is about 6 MB, although maybe later when I do some progress on video compression, you can store some minutes of video on a floppy!

http://www.youtube.com/watch?v=gZIu10nIVuU

My initial idea of the next step, compressing the video, is very simple: I refresh only 1/8 of each frame when playing.
I will do this by refreshing one pixel high rows (32 bytes) on the Spectrum's screen.
Some software, probably on the Spectrum, will use some time to compare each frame to find out which rows need to be refreshed first, which rows have the most changes.

If the playback routine is not fast enough I may try to use the Z80DMA on my MB-02 ;)