nickerso@dalcsug.UUCP (Scott William Nickerson) (01/13/88)
The following utility program is presented for the C-64 computer although
versions for the 128 and VIC can be easily derived.
A common problem when writing interactive programs which require that
instructions or other text be output for the user is that the print statements
must be carefully arranged so that words will not be broken at the edge of the
screen. This can be time consuming and if a minor change must be made to some
text it can affect the alignment of several other lines of output. This
program is very brief but provides the user with a very useful alternative to
this situation. No new commands are required as the whole routine is wedged
into the normal print vector of the machine. Run-Stop-Restore will remove the
wedge and a simple SYS will put it back in place.
Begin by loading the short BASIC program below which will POKE the ML
routine in place. This may be included as a subroutine in your application or
you may use a monitor to save the resulting object code and just load it from
your other programs.
*** THE PROGRAM ***
1000 data173,66,253,141,196,192,173,67
1010 data253,141,197,192,169,46,141,38
1020 data3,169,192,141,39,3,169,0
1030 data141,195,192,96,173,66,253,141
1040 data38,3,173,67,253,141,39,3
1050 data169,0,141,195,192,96,142,191
1060 data192,140,192,192,141,193,192,172
1070 data195,192,153,198,192,238,195,192
1080 data201,13,240,16,204,194,192,240
1090 data53,174,191,192,172,192,192,173
1100 data193,192,24,96,174,195,192,202
1110 data240,11,32,113,192,173,195,192
1120 data205,194,192,240,5,169,13,32
1130 data188,192,169,0,141,195,192,240
1140 data216,162,0,189,198,192,32,188
1150 data192,232,136,208,246,96,201,32
1160 data208,6,32,113,192,76,106,192
1170 data136,185,198,192,201,32,240,9
1180 data136,208,246,172,194,192,200,208
1190 data233,140,195,192,32,113,192,169
1200 data13,32,188,192,162,0,172,195
1210 data192,200,185,198,192,157,198,192
1220 data232,204,194,192,208,243,142,195
1230 data192,76,73,192,108,196,192,255
1240 data1,13,40,0
1250 forad=49152to49347
1260 readx:pokead,x
1270 next
1280 rem to activate use sys 49152
1290 rem to remove use sys 49180
N.B. - you may wish to use some kind of
"dynamic keyboard" technique to enter this
program as a text file rather than typing
it in.
To activate the wedge use SYS49152 in your program. This will be required
to cause all subsequent output to be buffered. By calling SYS49180 you can
remove the wedge so that the PRINT statement will behave normally. Any
characters which are printed are not output immediately but rather they are
stored in a buffer. When a carriage return is received or the buffer becomes
full the line will be output. This routine will also work if the output is
being directed to the printer or the disk. Since anything you print is placed
in a buffer make sure you empty it by sending a carriage return or a
SHIFT-carriage return at the end of any output message.
Below is a short BASIC program and the output that would result as viewed
on a 40 column screen:
10 PRINT"THIS IS A TEST OF THE SCREEN FORMATTING WEDGE PROGRAM. NOTICE ";
20 PRINT"THAT THE USER DOES NOT HAVE TO WORRY ABOUT WHERE WORDS END AS ";
30 PRINT"THE PROGRAM WILL FORMAT ALL OUTPUT AND LEAVE NO BROKEN WORDS TO ";
40 PRINT"WRAP AROUND THE SCREEN. THE RESULT IS VERY READABLE OUTPUT WITH ";
50 PRINT"NO TIME WASTED IN PROGRAMMING."
This is how it would appear if run without the wedge:
THIS IS A TEST OF THE SCREEN FORMATTING
WEDGE PROGRAM. NOTICE THAT THE USER DOE
S NOT HAVE TO WORRY ABOUT WHERE WORDS EN
D AS THE PROGRAM WILL FORMAT ALL OUTPUT
AND LEAVE NO BROKEN WORDS TO WRAP AROUND
THE SCREEN. THE RESULT IS VERY READABL
E OUTPUT WITH NO TIME WASTED IN PROGRAMM
ING.
This is how it would appear with the wedge:
THIS IS A TEST OF THE SCREEN FORMATTING
WEDGE PROGRAM. NOTICE THAT THE USER
DOES NOT HAVE TO WORRY ABOUT WHERE WORDS
END AS THE PROGRAM WILL FORMAT ALL
OUTPUT AND LEAVE NO BROKEN WORDS TO WRAP
AROUND THE SCREEN. THE RESULT IS VERY
READABLE OUTPUT WITH NO TIME WASTED IN
PROGRAMMING.
The program as is works on a 64 but can be easily converted for use on
a 128 or VIC. Questions or comments welcome through mail.