DDE - Controlling T4 via DDE Commands

Modified on 2013/01/16 17:05 by Andrew Busby (CTS) — Categorized as: Uncategorized

You can control some aspects of the T4 frontend via DDE commands. These are aimed at people programming applications within Excel that interact with T4.

Opening a Contract Window¶

You can cause T4 to activate or open a Contract window with a specific market displayed. To do this you need to enter the following in a cell:

=T4Screen|'CW_<MarketID>'!SHOW

where <MarketID> is the id of the market to display.

e.g. =T4Screen|'CW_CME_20130700_OZCN3_SPACE_C0680'!SHOW

Sending this command will cause the frontend to look for the most recently used Contract window for that Contract and bring it on top of any other application, making the specified market the active market. If no Contract window is found for that Contract then it will open a new Contract window and display it with that market active.

If you wish to repeatedly display the same market (e.g. user clicks a cell to display the contract window, then closes the contract window and clicks the cell again) then you need to replace the above cell contents with:

=T4Screen|'CW_<MarketID>'!CLEAR

where <MarketID> is the id of the market.

This clears out the last command processed and will allow the previous command to be sent again as a new command.

If the command succeeds then the value '<Command Succeeded>' will be returned to Excel, if the market is not found then '<Market Not Found>' is returned.

Changing the DDE Advertise Interval¶

You can change the timer interval that DDE advertisements are sent on. An advertisement is sent when a piece of data you are interested in has changed, e.g. last trade price. This is set at 10ms by default. If you want to slow down the updates then you can change this to be anything up to 60,000ms.

To change the timer you need to enter the following into a cell:

=T4Screen|'TMR_<Interval>'!SET

where <Interval> is the timer interval to set, in milliseconds, between 10 and 60000.

e.g. =T4Screen|'TMR_500'!SET will set the timer interval to be 500ms.

If the command succeeds then the value '<Command Succeeded>' will be returned to Excel.

If you close T4 desktop and reopen it then you would need to execute this command again for it to take effect.