8-bit Software (c) Duncan Webster April 1992
Issue 19 (c) April 3rd 1992.
PRINTING HASH CHARACTERS (user guide)
Program = HashGen.
This Basic program generates a machine code program to enable a
parallel printer with software selection of national character sets
to correctly print CHR$(35) as 'hash' and CHR$(96) as 'pound' on
both screen and printer.
The machine code program sits at &900 and works with any language
or application which does not make use of page &9. Its name is
chosen by the operator when it is assembled by the Basic program.
The routine is loaded by typing *<filename> when it is immediately
enabled. This should be done when the printer is disabled and the
ENGLAND character set selected. The routine can be temporarily
disabled by function key f0 (giving the screen message '*CODE 0'),
following which it may be re-enabled by function key f1 (giving the
screen message '*CODE 1'). These keys should only be used while the
printer is disabled. Alternative function keys may be specified by
altering lines 680 and 690 in the Basic program.
The machine code program will be corrupted by any use of page &9,
e.g., by any use of the series port or the cassette port, or by the
presence of any other machine-code routine using that page. It will
not work in the presence of a program denying use of the command
line vector. It should also be noted that the program alters the
contents of both the user vector and the write-character vector,
which may give rise to incompatibilities. Problems may also be
expected if used with those VIEW printer drivers which include a
'pound' printing function. This last difficulty can be avoided by
disabling the routine, with function key f0, when in VIEW's command
screen.
The program is disabled by <BREAK>, when it will be found that a
'Bad Command' message will be produced if function key f0 or f1 is
pressed. (This is due to vectors defaulting.) The program may
normally be re-activated by entering <CALL &900>, if necessary
after first re-entering Basic.
Dr. H. Clarke.