http://www.digitalgametechnology.com/index.php/support1/manuals/clocks/dgt2010-na
The manual is there. From what I can tell, it doesn't automatically add the time at move 40, nor can it be set to do that. So, the player would be responsible to claim if 40 moves were not made in the first time control since the clock will automatically add the secondary time control, when time runs out in the first.
Looks like mode 19 will do that.
So, the manual doesn't show that the move counter can be set, except in the Canadian Byomi mode, but they do have the following note the bottom, so I guess it might be an option in the custom time options:
If the move number is set to a non-zero number and a player does not complete the required programmed (non-zero) number of moves in any period, the DGT2010 will freeze and time counting is
stopped for both players and the game has ended. On the side of the player that reached 0.00 a
blinking flag will be shown to indicate that this player lost the game on time. Using the move counter in this way means that the players must take great care to correctly press the clock after each move.
FIDE does not recommend using the move counter method for transition to the next period. Instead
transition to the next period when 0.00 is reached, is the preferred method. It remains the responsibility of players and arbiter to check whether the correct number of moves has been played in any period.
But all the games i played in that tournament were in DGT2010 and it automatically added 30 minutes after 40 moves! Neither of us claimed
Ah, I did miss it on mode 21. You can set moves there. So, you would set the first time period, then the increment for all time periods, number of moves for first time period, then the second time period and leave the move counter at 0 and leave the third and fourth options at zero.
That said, that is not the recommended method FIDE suggests. Players should be required to claim, if there is a need and should not rely on the clock move counters.
Neither FIDE nor USCF Rules require to freeze time at any intermediate time period. FIDE Rules require to freeze time at last time period only.
It means, if a clock could count moves in given time control mode and you could see moves' counter on display (maybe by pressing a corresponding button), you actually don't need to set it in time control itself.
In your example you simple need to set two time periods (90 and 30 min) and set an increment in 30".
At the end of first time period a fallen flag will be visible during 10 minutes on a side who reached it first. It's enough to make a claim by players (USCF Rules) and/or by TDs (FIDE Rules).
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