Flipping vs. Swapping Screens in CodeView

ID Number: Q24201

1.x 2.x 3.00 3.10 3.11 3.14 | 2.x 3.00 3.10 3.11 3.12 3.50

MS-DOS | OS/2

Question:

What is the difference between flipping (/F) and swapping (S) in

CodeView?

Response:

Both are ways of maintaining two alternate screens for display on one

monitor. The difference is in the way the task is accomplished.

When swapping is selected, CodeView allocates a 16K buffer (a 4K

buffer for a monochrome adapter) to hold the alternate screen. When

the other screen is required, CodeView swaps the screen into the

display buffer and places the other screen into the storage buffer.

Swapping takes memory and time but it does not have the limitations of

flipping.

Flipping uses the video-display pages of the graphics adapter to store

each screen of text. When the alternate screen is required, the other

page is selected. Flipping is much faster than swapping and does not

require the 16K buffer. However, it cannot be used with a monochrome

adapter, or with programs that display graphics or use the video

pages.

Additional reference words: 1.0 1.00 1.1 1.10 1.11 2.2 2.20 2.30 2.30

2.35 3.0 3.00 3.1 3.10 3.11 3.12 3.14 3.5 3.50