HeadFirst Errors

By Gareth Boden

Originally published in EUG #08

Thanks for the review in EUG #7. Unfortunately there were two mistakes. The first, although less important, may lose us custom - we do sell both DFS and ADFS disks now and the "send your own disk and it only costs 75p" service has been dropped. The second is that you put the wrong address inside the magazine although the correct one is in the Electron Supply Addresses column. 45 Cedar Street is my address, 97 Chester Road is Headfirst's.

Having said that, I thought the mag was even better than its usual high standard (creep, creep!) and I particularly liked Gareth Babb's articles.

Please let me add my voice to the ever-growing chorus of conflicting views regarding the disk argument. Firstly, people seem to be a little confused about "Can't Extend" and "Compaction Required". The two are given in totally different situations:

"Can't Extend" is given only by DFS and occurs only when dealing with open files (not with loading/saving). Basically, if you have a file that is say, 10K long, and you then save another file after it, the DFS is not capable of adding extra bytes using BPUT to the first file - you get a "Can't Extend" message. The only solution is to copy the first file to another disk, delete the original, compact the original disk, and then copy it back and try again (Phew!).

Both DFS and ADFS are capable of storing files in the place of old deleted files (so long as the new file is shorter or of the same length as the space). However, if there is enough space on the disk, but not in portions big enough, the DFS gives a "Disc Full" message. ADFS is more intelligent and only gives a "Disc Full" message if there is not enough space on the disk. "Compaction Required" is the message given if the space is too fragmented.

Personally I prefer to use PEGASUS DFS on the Elk, even though PRES ADFS is more powerful. It is much quicker to use, leaves OSHWM at &E00, has all utilities in ROM and requires less brain power! On more powerful computers like the Arc and on a hard disk, ADFS is the logical choice.

Re: M. G. Manning's request for MODE 7 and DATABASE stuff. If he only wants a MODE 7 emulator for BBC BASIC programs or his own programs (and, let's face it, that is all that is likely to run on an Elk anyway!), ours may be just the thing. Our Database is more suited as an address database or something like that - it's not really powerful enough to use for cataloguing.

Does anyone else's Electron work perfectly? Mine is in a permanent state of fine balance! I have had trouble with the ULA since about six months after I bought it (in 1985) requiring me to undo its little carrier and waggle about a bit. Eventually last year I managed to break the carrier and so a new one had to be fitted. All was well until... well, I'm still having problems. In Turbo/64K mode, the screen display freezes even though the computer goes on working, and in Normal mode it just crashes altogether. Needless to say, this does not make preparing HeadFirst PD disks very easy...

Re: Tape Troubles. First, the Acorn Data Recorder is not the best system to use!!! I've heard many a sorry tale of woe about these little beauties!! People seem to me to be worried about head alignment. No-one I know has had to fiddle about with it to get tapes to load - the usual problem is the volume. At present I use the cheapest mono tape recorder I could find (ALBA DR-160) with a 7-pin DIN to 3 jacks lead and it works beautifully with most tapes. The simplest solution is get a disk drive!

Regarding updates. An Acorn 32-bit computer is the logical one because it is so similar to use. The old star commands are there, ADFS is the same, and the BBC emulator will run loads of your old programs (It'll even read your ADFS disks straight off!). I use one quite a lot and I would recommend it above a PC to anyone.

Finally, could I please remind readers that if they want a printed catalogue they should send an SAE. We will have to put disk prices up if we keep having to fork out for postage and/or envelopes! Could I also ask readers to send in any PD they may have, whether they have written it themselves or got it from another library. We can't support the Elk if you don't help us to do so - we're not capable of churning out program after program ourselves.

Gareth Boden
HeadFirst Public Domain