1 DFS 0.90
Strange effects are sometimes encountered when using DFS 0.90 with
When using multiple surfaces the disc catalogue can be written to an
incorrect surface. This is manifested by the 'Disc changed' message on
returning to command screen followed by drive 0 apparently being overwritten
with the files from drive 2.
Some problems can occur when building indexes.
The solution is to upgrade to Acorn DFS 1.2, 1772 DFS or ADFS.
To enable Utility Label to prompt for use of select file you need to prepare
a patch file as follows:
?&2800 = &FF
*save patch 2800 + 1
Then immediately before using utility Label enter:
*Load patch 50
Label with then give the 'Use Select file (N,Y)' prompt.
3 Entering records
On Viewstore 1.0 it is good practice when entering record to frequently
force Viewstore to write the records to disc. This can be done by pressing
CTRL and DOWN ARROW. This will write all of the new records safely to disc
and reduce data corruption problems.
4 REPORT format file prefix
On Viewstore 1.0 different prefixes are required at different times when
using report format files. When editing report format files the format file
is treated as a database and uses the Data prefix. However, when using the
report format file in the report utility it is treated as a format file and
so uses the Format prefix.
5 Running out of room in REPORT
Report format files can grow very large which can cause memory problems when
using them in utility report. Their size can be significantly reduced by
running them through utility Convert after editing them. In convert reply
Use select file (N,Y)? N
Field 1? * RETURN
Field 2? RETURN
Record size? +20
New filename: r.newfilename
6 Minimal space after setup
In Viewstore 1.0 it is occasionally possible for the Space field at the top
of the database display to be a small number eg 11 rather than the several
thousand bytes which it should be. This can be rectified by making an entry
eg +30 in the record size field in the database header.
7 Indexes on entering data
Remember to index by entry when entering new data. This gives faster
response tines and reduces the likelihood of index corruption on an
unexpected error like disc fault.
8 Database drive
Remember not to leave any files after the data file on the data drive. This
reduces Can't extend problems on DFS.
Remember to copy the special format file F.REPORT from the utilities onto
your format file disc before editing report format files.
10 Selecting on blank fields
When using Select you can match a blank field by giving the criterion field
11 Importing corrupt databases
If a database is corrupted for any reason, for example if you lose the end
marker or get 'Bad File' you can generally recover all or almost all of your
data by importing the database into another file. This is often much
quicker than retyping although you can, of course, refer to your backup.
12 When using ADFS with Viewstore
The error COMPACTION REQUIRED ON CHANNEL 57 can be encountered.
ADFS, if extending a file must keep the file contiguous. For example, if
there is no space after the file, it copies the file into an area where
there is more space. The free space on the disc must be larger than the
file being expanded.
Copy the large file onto a blank disc. Delete the file from the main disc.
Compact the disc. Copy the file back. It should now expand OK - BUT in an
application such as this it is very sensible if largest files kept on a disc
on their own.
13 SELECT syntax
Remember to use brackets and delimiters in select criteria. For example:
rrp/VAT=number and =10000
is unlikely to have the desired effect. You should enter:
("rrp/VAT"=number) and (" "=10000)
to be completely ambiguous.
14 Sort memory
Before running utility select to sort a file on the Model B remember to
enter mode 6 or mode 7 to give the greatest available memory for the sort.
15 Highlighting part lines in REPORT headers
To highlight part of a line in a report header do the following. Type the
header line into the report and insert a single @ character at each point
you want the highlighting to vary. Then in the field list enter a comment
specifier for each @ and succeed the comment specifier with the highlight
codes. For example:
Type Half1 Field list
H Ordinary@Bold@Ordinary 333,@1,333,@1
C Press RETURN
When Viewstore reaches the first @ it sends the first three highlight 3s to
the printer driver which will switch on emboldening. It then replaces the
first @ by comment 1. The user is prompted to press RETURN for the first
comment which will fill the comment with spaces (one in this case). The
word underlined will then be printed in bold before the emboldening is
switched off and another blank comment is printed.
16 Editing REPORT format files
Report format files can be edited in the View word processor. Read the
report format file into View and insert a ruler at the top of the file which
has no right margin and tab stops set wide enough to align the field in
columns. Now edit the file. Be careful to keep the fields separated by the
correct number of tabs and make sure that the lines do not exceed 132
characters. Before saving the file delete the ruler at the top. Finally
import the file back as a database, field separator being 9 and record
separator being 13.
17 Final REPORT editing
Reports can be edited by spooling the report to disc, reading into the View
word processor, editing and printing from View.
18 Case sensitivity in Watford DFS
Some versions of Watford DFS do not allow a mixture of cases in
directory names. It is necessary to ensure all filenames specifications are
in the correct case. In particular utilities should be renamed from
directory "u" to "U".
19 Filesizes and Utilities
The Viewstore utilities all assume maximum filesizes of 65536 when
performing calculations on filesizes. In particular giving a size n of more
than 65536 bytes to reserve in the setup utility caused Viewstore to reserve
n modulo 65536 bytes. So specifying 70000 bytes will actually reserve 4464
bytes. This does not limit either the size of your database file or the
sizes of your index files.
20 Bytes to reserve - Load time tradeoff
On loading a database Viewstore quickly loads the format file, opens up the
data file and reads it from the end of the file backwards to the end of the
data marker. If there is a lot of space at the end of the file this may
take a little time. Consequently unless you need space reserved at the end
of the data file (if you are using a single DFS surface) it is best to
reserve 0 bytes when setting up the database.
21 Writing utilities
It is possible to write extra utilities for use with Viewstore.
However, this should only be attempted by experienced 6502 programmers who
either require a utility for special use or who are planning to exploit the
utilities commercially. Acorn have no copyright restrictions on others
selling their own Viewstore utilities.
All of the code and documentation supplied with Viewstore is subject to
English copyright law. You are not allowed to copy the Viewstore EPROM
without explicit permission from Acorn. You may copy the Viewstore utility
disc for your own use.
23 This is a BASIC utility that enables you to append one database to
another in Viewstore
The simple format of Viewstore database files enables simple manipulation by
programs written in BBC BASIC. For example, the following program appends
one database file to another.
NOTE: the field order within records of both databases should be the same
for sensible results.
10 INPUT "File 1",file1$
20 INPUT "File 2",file2$
30 one=OPENUP(file1$) :REM BASIC 1 users should use OPENIN
50 REPEAT UNTIL BGET#one=1
100 UNTIL byte=1
24 Obtaining Reports from a database (This is an example)
Whether or not you have prepared a Select File when running the SELECT
utility, you can produce a simple report on screen of the first 80
characters of each record, or if you choose the printer option, you can
specify the width of the paper, page length and whether or not single sheets
are required. The simple report will give all the records or a selection,
depending on whether a Select File is used. If you follow the Report
Utility routine through without using a Report Format File (answer N to the
prompt "User report format file N,Y?") you will see that this 'simple'
report is not particularly suited to the chosen layout of your data in th
name and address file. The key factor here is that the records are shown in
the spreadsheet format, and are thus limited to the width of the screen
(usually a max of 80 characters), or the specified paper width if you choose
the printer option, so once again you are not going to see all the data from
the database, there are some sorts of database for which this type of
report is perfect (such as accounting applications) where you might use a
spreadsheet style display for the database and limit the width to 80
characters anyway, in which case this form of reporting is perfectly
The above is suggested as a guideline and we hope that this will enable you
to setup a report specifically for your printing requirements.
25 Printing labels from a Viewstore database using label utility
The Label Utility enables you to extract information from a database for
printing labels. First load the database from which you want to print the
labels and ensure that the computer has been prepared for printing. You
will notice on the screen after loading the database:
Editing D.(database filename)
Format F.(format filename)
Then type: UTILITY LABEL (press return)
The Utility Label program will ask you various questions that you should
answer as below:
Use select file (N,Y)? (type N if this applies to the whole
database or Y is to select file)
Screen or Printer (S,P)? P (RETURN)
Label height (lines)? 6
Lines between each label? 3
Width of label? 25
Characters between each label? 6
Number of labels across the page? 3
Line 1? )
Line 2? ) enter the field name or names from which information
Line 3? ) has to be extracted. Where there is more than one field
Line 4? ) name required this must be separated by commas
Line 5? ) eg Name, Address
Line 6? )
26 Using Viewstore convert
1. 'Convert' converts an existing database, or a SELECTED subset into a new
file. To add a space to an existing file use:
Use Select file (N,Y)? N
Field 1? *
Filename? (a new name)
Record size: +100
Then use LOAD (new name) (old name) to use the new database, with the old
format file, or rename the (new name) to (old name) (backing up the old file
2 Printing out some fields or a file is done with the REPORT Utility - see
the manual for details.
3 Furthermore, if you want to pass an alphabetically sorted database to
View it is done by SELECTing the fields you want, sorting on the appropriate
field, then using CONVERT, this time with a select file, to produce a new
database in sorted order, which can be passed to View.
27 This applies to View and Viewstore (PDG)
Although View has only two highlight codes these can be redefined using HT
code in "Edit command" (Shift F8) to make use of other features available on
the printer. The actual values associated with the highlight codes can vary
from 128 to 148.
If you want to access extended characters you use HT 2 130. This is entered
in your View document using Shift F8 (Edit command). However, you should
enter the appropriate codes in response to the printer initialisation
question in the PDG.
For example: In View to change font you would enter *-- (means Highlight
2,1,1). View then sends to the Printer Driver 130 128 128 codes to switch
to the new font.
With Viewstore you would need to put these codes in REPORT FORMAT file 3 1
1. Viewstore sends to the Printer Driver 127 + number (130 128 128).
28 Viewstore import procedure - Viewstore to Viewstore
Source file D.(filename)
Destination file :(drive number).D.(new filename)
Position in file where data starts 0>RETURN<
Record Separator 13 (carriage return in Viewstore)
Appears before first record N
Appears before last record Y
Field Separator 9 (tab character in Viewstore)
Before first character N
After last character N
End of file marker 0
Is data reserved N (it is in database)
Trailing character to skip N
Record size <RETURN>