Tandy 600 Programmer's Reference Manual page 29

FUNCTION 2Dh
-
Set
Time
AX:
BX
CX
DX
XXXXXXXX
XXXXXXXX
XXXXXXXX XXXXXXXX
XXXXXXXX
XXXXXXXX
SP:
BP:
SI:
Dl:
IP:
FLG
CS
DS
ss
ES
Entry
Exit:
AH =
2Dh
(function
code)
CH =
Hours
CL =
Minutes
DH =
Seconds
DL
=
Hundredths
of
seconds
AL =
status
code
Function
2Dh
is
used
to
set the current time
in
the operating
system.
The
format of
the
parameters
is:
CH
CL
DH
DL
-
Hour
(0-23)
-
Minutes
(0-59)
-
Seconds
(0-59)
-
Hundredths
of
seconds
(0-99)
On
return,
the carry flag
will
be
reset
if
the operation
succeeded.
If
the carry
flag
is
set,
the
operation failed
because
of
an
error in
the specified time.
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