DTJulianMillisecToQwordDateTime

Converts Julian date integer value and total milliseconds to QWORD values containing date and time information. On return RAX contains the date information and RDX the time information.

DTJulianMillisecToQwordDateTime PROTO JulianDate:QWORD, Milliseconds:QWORD

Parameters

JulianDate - A QWORD value containing the Julian date integer to convert to a QWORD date in RAX.
Milliseconds - A QWORD value containting the total milliseconds to convert to hours, minutes, seconds and milliseconds in QWORD time in RDX.

Returns

On return RAX will contain the date information in the following format:

RAX Register Bits:

+--------------------------------------------------+------------------------+------------+-----------+
| DWORD                                            | WORD                   | BYTE       | BYTE      |
+--------------------------------------------------+------------------------+------------+-----------+
| Bits 63-32                                       | Bits 31-16             | Bits 15-8  | Bits 7-0  |
+--------------------------------------------------+------------------------+------------+-----------+
| Not used - Not applicable                        | Century Year           | Month      | Day       |
+--------------------------------------------------+------------------------+------------+-----------+
| N/A                                              | CCCCYY                 | MM         | DD        |
+--------------------------------------------------+------------------------+------------+-----------+

On return RDX will contain the time information in the following format:

RDX Register Bits:

+--------------------------------------------------+------------+------------+-----------+-----------+
| DWORD                                            | BYTE       | BYTE       | BYTE      | BYTE      |
+--------------------------------------------------+------------+------------+-----------+-----------+
| Bits 63-32                                       | Bits 31-23 | Bits 23-16 | Bits 15-8 | Bits 7-0  |
+--------------------------------------------------+------------+------------+-----------+-----------+
| Not used - Not applicable                        | Hour       | Minute     | Second    | Millisec  |
+--------------------------------------------------+------------+------------+-----------+-----------+
| N/A                                              | HH         | MM         | SS        | MS        |
+--------------------------------------------------+------------+------------+-----------+-----------+

Notes

The registers always return the information in the format shown in the tables above.

Example

.data?
qwDate dq ?
qwTime dq ?
Year dw ?
Month db ?
Day db ?
Hours db ?
Minutes db ?
Seconds db ?
Millisec db ?

.code
Invoke DTJulianMillisecToDwordDateTime, 2299161, 0
mov qwDate, rax ; rax contains the date information
mov qwTime, rdx ; rdx contains the time information

mov rax, qwDate
shr rax, 16 ; move year into upper word of eax
mov Year,  ax ; year
mov rax, qwDate
mov Month, ah ; month
mov Day, al ; day

mov rax, qwTime
shr rax, 16 ; move hour and minute into upper word of eax
mov Hours, ah ; hours
mov Minutes, al ; minutes
mov rax, qwTime
mov Seconds, ah ; seconds
mov Millisec, al ; millseconds