I have created a GEOS application based on this code here. If you download the zip file you will also get the source code in plaintext format.
My code to read the time from the Ultimate can be found here (plaintext).
This will just read the time but maybe that will help you create code to set the time in the Ultimate.
P.S. There is a PDF that includes the DOS commands (ultimate-dos-1.2.pdf), here is the part for the RTC-commands:
QuoteDisplay More2.24. DOS_CMD_GET_TIME (0x26)
Command format: $01 $0x26 [ id ]
This command returns the current date and time and the status channel will read “00,OK” on success.
If no argument is given or if the argument is zero, the format is “yyyy/mm/dd hh:mm:ss”.
If the argument is one, the format is “www yyyy/mm/dd hh:mm:ss”, i. e. it contains the day of
the week, too.
This command has been introduced in version 1.2.
2.25. DOS_CMD_SET_TIME (0x27)
Command format: $01 $0x27 <Y> <M> <D> <h> <m> <s>This command sets the current date and time and the status channel will read “00,OK” on success. The year has to be reduced by 1900 in order to fit in a single byte.
This function may be enabled or disabled by the ultimate settings. In the latter case the status will read “98,FUNCTION PROHIBITED”.
This command has been introduced in version 1.2.
The command interface is described here.
P.S. The "T-RA" commands are part of the CMD drives/DOS like CMD-HD or CMD-FD, i don't think the 1541 will support these commands since the 1541 does not have a RTC. If you need to read/write the time of the Ultimate you need to use the DOS commands described above.
Maybe someone else has a BASIC example for that.
So, how to read and write real time clock of 1541 Ultimate? Computer used is Commodore 128 DCR.
ultimate-dos-1.2.pdf
The pdf can you found at: https://github.com/markusC64/1541ultimate2 Directory "doc"
Maybe someone else has a BASIC example for that.
A simple BASIC example (read clock from 1541UII(+) ) is here: Ultimate DOS
Well, please note that the BASIC example has some bugs in it... especially in the waiting loops. Basic is so slow that it does not make a difference in my test.
