EUG PD


Utilities And Agreement

 
Published in EUG #52

Sorry for the radio silence - busy doing my final year project in York. Any readers with web sites, please ensure that, if you're linked to my York address, you change to http://www.sprow.co.uk/bbc

On this EUG disk, you will find two utilities from me: LISTO and an update to the RAM filing system which was published in EUG #50. Inspired by Chris Warburton's generic sideways ROM header generator, I created the first as a new list option for BASIC and bit 3 in LISTO allows multi-line statements to be split up. Full documentation is included but basically lines such as:

      100AND#127:STXj2%:TSX:CMP&105,X:PHP
      110LDXj2%:PLP:BNEstarcmp:LDXj1%

become:

      100AND#127:
         STXj2%:
         TSX:
         CMP&105,X:
         PHP
      110LDXj2%:
         etc...

This can be used in conjunction with other list options. See the BBC User Guide for LISTO options in bits 0..1..2.

I haven't bothered to submit all the documentation for RAMFS again as I assume most readers will have the EUG #50 disk articles to refer to. However, the new version on the U directory on this disk has bug one fixed and is up to 50% faster for sequential ops, allowing 21.7kb per second.

Onto other things. In EUG #51, John Crane commented on LS120 drives which, for those who missed it, are drives that read/write their own 120Mb format and also Double Density and High Density floppies too.

Indeed, Acorn disks do start at track 0 (both DFS and ADFS formats) and PC disks have their boot sectors starting at track 1. I'm not sure what's inside these drives but if there's an off the shelf floppy controller chip, it would seem foolish for the manufacturer to not allow access to track 0...but when has foolishness ever stopped anyone?

The main stumbling block I see with LS120 drives is the EIDE interface. I challenge anyone out there to build a working EIDE interface for the BBC and write a filing system to steer it.

I think we should stick to SCSI where all the work is done by the hardware and the host computer just coughs a few commands down the 1MHz bus to do the work! Or pop it onto my RAM filing system (with up to 8Mb storage) with battery backup. That should be enough.

Iomega ZIP drives also look quite funky.

Finally, I recommend, as John did last month, buying a RISC OS-based machine to run alongside your BBC (switches channels on his TV card to the AV input to check the BBC's still working OK then switches back to the 9 o'clock news).

Robert Sprowson
E-mail: info@sprow.co.uk
EUG #52

Robert Sprowson