Subject : *Compact using ADFS 1.3x
Machine : BBC model B (no shadow RAM)
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Several years ago (back in the mid 1990's), ADFS 1.30 reported "Compaction recommended" I ignored it (as you do). I thought, 'How can this 30Mb hard disc need compacting?? It still has tons of space!!!'.I didn't realise back then that the free space map held the key to compaction, as the number of entries contained within were (and still are) finite. Anyway, eventually ADFS 1.30 gave up asking and suddenly demanded "Compaction required" I thought 'Oh well (and sighed preparing myself for hours of time taken up by the process). With baited breath, I typed *COMPACT, and was instantly reduced to tears. Yes real tears!!! Despite most of the programs that I'd written being complete rubbish, I hated the idea of them being them lost forever with all the hours I'd spent / wasted on them. Below are two IDE CF card reconstructions. Mode 7 (the mode I used) on the left left and mode 2 (for Rick Murray) on the right. The drive doesn't need compatcting, but in the 30 second clips, you will see why I paniced
After several hours, the HD activity ceased and to my surprise the beeb became responsive despite the screen still being a total mess. With beads of sweat still pouring from every pore and not forgetting those sore and salty eyes, I dared to type *CAT, *MAP, LO."xxxx" and it all worked :-) (the clouds parted, and sun came out and I jumped for joy) . Why did Acorn do this to me? What a horrid bit of code. I know *now* that the compaction part of ADFS uses all available memory including screen memory, but back then it really would have been nice to have been warned. I guess that this was an oversight assuming they converted 1.30 from ADFS 1.50 (with it's use of shadow RAM). I assume 1.50 came first?