Disc System User Guide (1982).

More documents

Recommendations

Info

more detail later. Now press SPACE to continue. This will run the series of demonstration programs supplied on the disc. When the > prompt reappears on the screen you can start entering your programs or filing system commands, but before you do that, read the next two chapters 'Discs' and 'Disc Files'. Diagram 1 Connecting the disc drive
3 Discs The BBC Microcomputer uses 5.25" discs for storing information. You may have heard them referred to as 'floppy discs', 'discettes', or 'mini-discs'; we will always refer to them simply as discs. (The American spelling is disk.) Two types of disc drive are available for the BBC computer, a single unit ( 100K/bytes) and a dual unit (800K/bytes). Discs used on one type will not work on the other. A disc from a single drive will store about 100 000 characters, equivalent to 50 pages of this book. Discs from a dual drive unit will store about 400 000 characters each. It is possible to use two single disc drives linked together providing space for storing about 200 000 characters, but this is not a standard option. Handling Discs should be handled with care to avoid physical damage or damage to the recorded information. Diagram 2 will help you to identify the various parts of the disc that we are referring to. The following guidelines should be observed: — Do not try to remove the circular magnetic disc from the square, black protective jacket covering it. — Do not touch the exposed recording surfaces. — Avoid dust. Put the discs back into their envelopes when they are not in the disc drive. — Do not bend them, drop them on the floor or put heavy objects on them. — Keep them in a storage box designed for the purpose. — Keep them away from strong magnetic fields such as those generated by televisions, monitors, tape recorders, telephones, transformers, calculators, etc. — Avoid excessive heat, moisture and direct sunlight. — Only use felt-tipped pens to write on the labels and don't press hard. — Insert discs into the drive carefully. If it rotates noisily open the drive door and adjust it. Information is packed quite densely onto the disc, so it is sensitive to even very small scratches and particles of food, dust or tobacco. The foregoing is deliberately comprehensive but do not let it frighten you from using the discs. Handled sensibly, a disc will give good service. 13
Page 4 and 5: ©© Acorn Computers Ltd 1982 First
Page 6 and 7: 9 Changing filing systems 75 10 Err
Page 8 and 9: 1 What is a disc system? If you hav
Page 10 and 11: computer the name of the file conta
Page 12 and 13: — The disc filing system controls
Page 16 and 17: Diagram 2: A 5¼" disc
Page 18 and 19: to copy a complete disc or specifie
Page 20 and 21: Diagram 4 Single disc drive copying
Page 22 and 23: Diagram 5 Tracks, sectors, bytes
Page 24 and 25: The drives are numbered as shown be
Page 26 and 27: Option 0: ignores !BOOT Option 1: *
Page 28 and 29: Notes Particular points to watch fo
Page 30 and 31: Important Locking a file does NOT p
Page 32 and 33: *BUILD Purpose To create a file di
Page 34 and 35: Notes Permitted values of are 0, 1
Page 36 and 37: Diagram 6 *COMPACT Warning This com
Page 38 and 39: *DELETE Purpose To remove a single
Page 40 and 41: *DIR () Set the directory Purpose T
Page 42 and 43: *DUMP Purpose Produces a hexadecim
Page 44 and 45: * EXEC execute Purpose This comman
Page 46 and 47: *INFO Purpose Displays information
Page 48 and 49: On entry X and Y point to a block o
Page 50 and 51: *LOAD Purpose Reads a named file
Page 52 and 53: *OPT 4 (n) Purpose Changes the auto
Page 54 and 55: *RUN (parameters to utility) Purpo
Page 56 and 57: If enough space is available, the i
Page 58 and 59: Displaying the file using *LIST wil
Page 60 and 61: *TYPE Purpose Displays a text file
Page 62 and 63: 6 The filing system utilities As ex
Page 64 and 65:
can format a disc in the second dri
Page 66 and 67:
7 Random access files One of the ma
Page 68 and 69:
this case the type is 'string' so t
Page 70 and 71:
The above method will only work con
Page 72 and 73:
A=&80 causes a file to be opened fo
Page 74 and 75:
A=0 Save a section of memory as a n
Page 76 and 77:
On Exit C clear implies a successfu
Page 78 and 79:
10 Error messages &CC Bad filename
Page 80 and 81:
&BD Not enabled An attempt is made
Page 82 and 83:
&07 Number of sectors on disc (8 lo
Page 84 and 85:
12 Filing system command summary Co
Page 86 and 87:
Index Abbreviations 82 *ACCESS 27 A
show all

Disc System User Guide (1982).

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?