Commodore VIC-20 - Page 154

140 The VIC 20 User Guide
line. The R VS ON control character precedes each PRINT statement line
number, and the
RVS OFF character follows it. These characters do not
display anything by themselves, and they do not take up space on
the'
display. They do change the display mode; that is, any characters following
the
RVS ON will display in inverse video. Likewise, any characters following
the
RVS OFF will display in normal video.
THE DATA ENTRY SEQUENCE
Once the entry lines are displayed, the entries start at the NAME line.
The program displays a black bar, showing where the entry should start, as
well as how long the entry will be.
The operator can back up on the entry line by pressing the
INSTjDEL
key to correct any typing errors. When the entry is complete, the operator
presses
RETURN and the program goes to the next entry line.
This data entry sequence translates into the following BASIC statements:
200 REM OET 12 CHARACTER NAME
210 R~.3:Cy'.9:LN~=12:GOSUB 8000
220 NAS-ce.
230 IF EDITINO~ THEN 500
250 REM OET STREET
260 Ry'm4:C~=9:LNY.=12:GOSUB 8000
270 SR'=CCS
290 IF EDITING~ THEN 300
380 REM OET 12 CHARACTER CITY
310 Ry'=3:C~=9:LN~=12:00SU! 8000
320 CI$=CC'
330 IF EDITINOY. THEN 500
350 REM GET 12 CHARACTER STATE
360 R%=6:Cy'=9:LN~=12:GOSUB 8000
370 IF EDITING~ THEN 500
400 REM GET 5 CHARACTER ZIP CODE
410 R~=7:C%=9:LN%-S:OOSUB 8000
428 ZI'=CC'
438 IF EDITINO~ THEN 500
450 REM GET PHONE NUMBER
460 R%=8:C%=9:LN~=12:GOSUB 8000
478 PH,=CC'
There is some uniformity to these statements, which are in six separate
groups. The groups start at lines 200, 250, 300, 350, 400, and 450, each cor-
responding to
an entry the operator is to make. Each group begins with a
REM statement.