Running Trends in RSLogix 5

Hi,
I am trying to gain some data by utilising the trend feature in RSLOGIX 5. I have a trend set up and I walk away. Its logging the data but every so often it comes up with following error message.
"Unable to bit blit". Does anybody know what this error means. did a search and couldn't find anything?

Funny error message huh?

This has happened to me a few times...
From RA free know-base:

ID 26224

Question TrendX Error: Unable to bit blit Cannot draw. Answer Problem:
The following error message appears in the Activity Bar while using RSTrendX ActiveX Controls.

TrendX Error: Unable to bit blit Cannot draw.

Cause:
Under most circumstances, TrendX is drawn to an off-screen bitmap and then the off screen bitmap is BitBlt()'d into place. This is done as a speed optimization, but if the BitBlt() fails, the cryptic error message about the BitBlt() failing is displayed.

Solution:
1). One option is to disable any screen savers which are currently being used while using RSTrendX. (this is the perferred solution)

2). The other option to suppress the error message would be to set the TrendX window style to transparent. When the window style is transparent, the drawing code can not use the off-screen bitmap for rendering and the BitBlt() call is not performed. The disadvantage with the transparent window style is that the drawing of TrendX is slower which can affect performance.

Additional Information:
Bit blit (bitblt, blitting etc.) is a computer graphics operation in which two bitmap patterns are combined into one. The name derives from the BitBLT machine instruction for the Xerox Alto computer, standing for "Bit Block Transfer". The pronunciation of BLT as "blit" dates back to block-transfer instructions on earlier computers. The development of fast methods for various bit blit operations was key in the evolution of computer displays from using character graphics, to using bitmap graphics for everything. Blitting is similar to sprite drawing, in that both systems reproduce a pattern, typically a square area, at different locations on the screen. Sprites have the advantage of being stored in separate memory, and therefore don't disturbe the main display. This allows them to be moved about the display, representing the "background", with no effect on it.

Blitting moves the same types of patterns about the screen, but does so by writing into the same memory as the rest of the display. This means every time the pattern is placed on the screen the display "under" it is overwritten, or "damaged". It is up to the software to clean this damage up by blitting twice, once to remove the damage, and then again to place the bit in its new location. As one might imagine, this makes blitting somewhat slower than sprite manipulation. However, blitting has one very big advantage, there's no physical limit to the number of patterns you can blit. Thus you can use blitting to display anything on the screen, including simulated sprites, whereas sprites are limited in number.

When first introduced the computers CPU typically had difficulty moving the bitmaps around in memory fast enough to be able to use blitting as the primary method of text display. For some time in the 1980's many home computers included either a co-processor or a special-purpose chip known as a blitter for this task. The CPU would send the bit blit operations to the blitter, which would then carry out the operation much faster than the CPU could. Modern graphics accelerators can be regarded as descendants of the early "blitters".
Problem: The following error message appears in Activity Bar while using RSTrendX ActiveX Controls. TrendX Error: Unable to bit blit Cannot draw.
Cause: Under most circumstances, TrendX is drawn to an off screen bitmap and then the off screen bitmap is BitBlt()d into place. This is done as a speed optimization, but if the BitBlt fails, the cryptic error message about the BitBlt failing is displayed.
Verify:
Cure: 1). One option is to disable any screen savers which are currently being used when using RSTrendX. (this is the perferred solution)

2). The other option to suppress the error message would be to set the TrendX window style to transparent. When the window style is transparent, the drawing code can not use the off screen bitmap for rendering and the BitBlt() call is not performed. The disadvantage with the transparent window style is that the drawing of TrendX is slower which can affect performance.
Prevention: Disable Screen Saver
Catalog Number:
DocFullNum: E57938295
Revision:N/A
Fixed in Revision:
Package:
Modual:
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Thanks, Screen Saver is causing it allright.

When you get this "Unable to bit blit" message you can press the minimize button on trend screen, then press the maximize button, and you will be able to see the current up to date trend data.