Hardware considerations

• One Flash card is needed for supporting OZ in slot one
• A second will certainly be necessary in slot 3 for file storage
• Internal RAM must be 128K, upgrade is very very easy to do for less than £5
• External RAM will be inserted in slot 2
• Minimum 128K for internal RAM will be explained further




Kernel

User Defined Interruption

An interruption could be available for applications. It could be done by addressing it via an handle. Opening, using... and closing an interruption. This should be a little fragment of code, copied in a special area of the system RAM. For implementing it, we could insert in the IM0 interruption (keyboard, serial port, card manager...) a fragment of code like this :



;the IM0 interruption entry
.int_entry
	ld hl,(interruption_address)		;this address is the code area
	ld a,h
	or l
	jp z,no_user_defined_interruption	;if zero, no user interruption installed
	jp (hl)					;jump to it
.no_user_defined_interruption
	...

Of course, it will only be a maskable interruption. It could be very dangerous but very useful too, for example, it could be the basis of the TCP/IP routine, refreshing a game screen...



Filing system : cluster of 256 bytes

Actually when the filing system is based on 64 bytes blocks. They are got from 256 bytes blocks allocated with the filing system handle, they are then divided in 4 parts and then formatted... Erasure, linking is very slow... These blocks must have 256 bytes like the allocated memory blocks, this would increase performance, reduce the FS code (very complex). That would be transparent for the end-user or the programmer because the Fileio routines would be the same.



Filing system : allow ROM/EPROM mounting

We could define a new way to access to files on ROM (not the file eprom format). That would be useful for using some files on the ROM, like the Printer drivers, the help, some useful Basic programs... Some directories would have a 'Read-Only' access and would contain some system files like printer drivers, help, config files...



Filing system : file attributes

The file attributes, already existing in DORs, should be implemented. Particulary, allowing Read-Only, System, Executable, Compressed attributes.



Internal RAM : 128K minimum

All the system RAM should be internal. No more screens or UDG on RAM.1, nor swap memory for bad applications. An amount of 64K is required, i.e. 4 banks :

• 8K for system variables, handles, buffers, restarts
• 2K for HIRES0, 512 bytes for LORES0, 2K for the screen base file
• 40K for the swap for bad applications
• 11K left for new purposes

The 11K left could be useful for new features like :

• other graphic screens (HIRES0)
• user defined interruptions
• the TCP/IP stack
• memory buffers allocated by a handle available for applications




Serial port : high speeds, TCP/IP stack

The 19200 and 38400 bauds speed are supported. Garry spoke about a TCP/IP stack. That would be a marvellous thing, probably very difficult to implement.



Keyboard : international support

In 1MEG we have enough space to store the various foreign keyboard and character tables. 'just' have to modify the jump of the keyboard scanning routine and the screen driver. Easy to say, hard to do... This could be changed from the Panel, saved in a config file read on soft reset.



ISO LATIN I character set

Each foreign version could have its own characters but it seems impossible to implement the whole character set wuth each font (normal, tiny, bold). The blink only supports 448 characters. A critical choice has to be decided... For more read 'ScrDrv.html'. The 'Euro' symbol is added.



RAM based applications support

The installer features are added as 'commands' in the Index. APu files are stored in a special directory. Now, you wont need external application cards anymore. Just load the files from the FlashEprom and install in RAM. If you wish to keep the application forever, just add it to the OZ rom with the RomCombiner.



New libraries

As described is 'OZ_calls.html', there is enough place to implement new OZ routines. These will support :
• Flash Eprom library
• Graphic library
• Sound library
• ZIP File compression library
• Large contigous memory block allocation library
• WAV play routine (and thus having a pretty bell)




Foreign system messages

We can dream... why not implement different langages for the system messages. It could be selected from the Panel.



System applications

Panel

Would be more pretty, more powerful by adding new features : Keyboard selection, Printer driver selection, keeping a system RAM image when saving (it could be recovered after a crash)



Printer driver editor

Would just edit the driver filter. A lot of different could be added directly in the Rom. These driver would include the full ISO translations, printers supported could be :


• IBM Proprinter
• Epson LQ
• HPCL
• Canon BJ




Filer

It would be boosted by the new filing system. Access to the Flash eprom device, with partitioning features. Allow 'on-the-fly' or not ZIP file compression.




Other applications

Pipedream



• Add the RTF format option for more compatibility.
• Accept the whole ISO LATIN 1 for sorting order.




Calculator

Add scientific options by implementing the FPP routines and adding some base conversions useful for programmers.



Diary

The Diary would benefit from being more word-processor-like in entering text. Currently, it is based around the GN_SIP system call which manages the input of a single line. The Diary should at least have wordprocessing facilities like PipeDream. Several Diary Applications are necessary as well - a single app is too limited. This is fairly easy, since only the DOR structure needs to be changed…



ImpExport

Imrove the transfer protocoles, and implement the Easylink protocoles. Why not use directly Easylink ?(If Gunther agrees).



BBC Basic

It would be nice to add the patch to the basic and create the BBC v4.0. I've the patch sources, I've began to do that, still some problems with ram variables. Menu could be added too (like FILE LOAD,SAVE, RUN...).



New applications

HTML browser

Started, much work has still to be done. Useful for help files viewing and, why not, web browsing.



WAV file player

I'd like so hear my lovely computer say 'Z88 forever!'



Text editor

Would be appreciated with a spell checker with some facilities, like compilator shortcuts, HTML tags...



Documentation

Sources

All the sources would be available on each release. They could be used under a license like the GPL. Just for lovers, no commercial use.



Help

All the help and developper notes must be maintained, it is the only way if we want to see new software or improvments. They should be written in HTML.

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