All the F keys transfer the input in the data window, the statement code column and statement line from the terminal to EDT. In addition, the keys [F1] to [F3] have special functions:
[F1] Positioning at records with the same structure depth
[F1] can be used in combination with the statement codes + and - to move to the next record with the same structure depth (see section “Statement codes in F mode”). [F2]
Setting all the screen lines in the data window to overwritable
If the screen is sent with [F2] then the data window, or both data windows if the screen is split, is set to overwritable on the following output.
When transfer is performed with [F2], if the entries in the statement line have not yet been executed due to the processing sequence observed by EDT, for example because both a statement and one of the statement codes 1..9, I or E (see the section dealing with the processing sequence) have been transferred with [F2] then the data window is first set to overwritable and the statement line is output again unchanged. The changes then entered in the data window become effective even before the processing of the statement line.
[F3] Processing record marks
[F3] in combination with the statement codes 1..9 and D or the scrolling statements +, - and ++, -- triggers the following functions:
Set record marks (statement codes
1..9)Delete record marks (statement code
D)Move to records with record marks (statements
+, -,++,--)