Radio Shack TRS-80 Model II Reference Manual page 157

Utility Programs
D ATM (Machine-Language Subroutine)
EXDATM (Console Program)
Date Calculations
DAT~1J1n
is a machine-language subroutine that performs date cal,cul.ations;
for 32K computers;
nn
=
64 for 64K computers.
EXDATMnn
is a console program (can
be
executed from
TRSDOS READY
mode) that loads
and uses
DATMnn; nn
=
32 or 64 as above.
EXDATM
is a console routine which calls the date calculation program
DATM
and allows you to pass data to it from the keyboard.
DATM
performs two functions:
1. Given a date and a timespan measured in days, the program adds the
timespan to the date and calculates the resulting date. The timespan can't
be greater than 65535 days; the year of the date must be at least 1600 and
not larger than 9999.
2. Given two dates, the program calculates the number of days between the
dates. The same parameter limitations apply.
Sample Uses
Under
TRSDOS READY,
type:
EXDATM64
or
EXDATM32
depending on whether you have a 64K or 32K machine. The program will
ask you:
DATE ADDITION OR DIFFERENCE
(AID) ..
Date Addition
To add a date and a timespan, type:
A
1:mi1n1
The program will ask:
ENTER PARAMETERS .
to which a sample reply might be:
05/14/1977(J018f!i4WFld
The program will compute and print the date which is 180 days after May
14,1977:
THU NOV 101977 314
followed by the system time. The number 314 means that November 10 is
the 314th day.of 1977 (see the
TRSDOS DATE
command).
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