Volume in TradeStation 4

["Allan L. Kaminsky" <allank@xxxxxxxxxxxxxxxx>]

I am using TS4, Build 20.

For an example, let's say I have a one minute chart on MSFT. If I open a
data window, I see date, time, OHLC, and volume listed in 2 different
columns: 'U', 'D' (presumably up and down).

Now, let's say I go into the edit tick window for MSFT, make an ASCII
file of the tick data, and then open that in Excel, for convenience.

The total of the U and D columns does indeed equal the sum of the tick
volumes. However, I am very hard-pressed to see how the assignment to
the 'U' or the 'D' category is made.

Does anyone have the definitive answer to this?

Allan