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HP Forum Archive 20

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15c LE - Another Flashing Display Issue
Message #1 Posted by Jeff O. on 17 Nov 2011, 1:09 p.m.

As has been documented (here and here for example), the 15c LE display will flash oddly in various situations. I discovered three more which I do not believe have been reported:

1. in complex mode, press f - (i) to temporarily display the imaginary component. While the temporary display is up, press a single digit key, as if you were starting to key in a number. As soon as the temporary display of the imaginary component goes away, the digit you pressed will be displayed, and the display will be flashing. Pressing another digit key will continue entry of a multi-digit number beginning with the one that was already entered, and stop the flashing display. Pressing any function key will execute the function on the flashing number and stop the flashing display. If you press more than one digit key while the temporary display is up, the flashing will not occur. On my 15C Classic, key presses during the temporary display are simply ignored.

2. in any mode, press f - PREFIX to temporarily display the full mantissa. While the temporary display is up, press a single digit key, and you will get the same behavior as above.

3. in any mode, press g - MEM to temporarily display the memory allocation. While the temporary display is up, press a single digit key, and you will get the same behavior as above.

I tried to think of other temporary display modes which might exhibit the above behavior and could not think of any. You can of course execute PSE from the keyboard which is a temporary mode of sorts. On the 15C Classic, keyboard input during the pause is ignored. On the 15c LE, input will be accepted as in the above examples and displayed after the Pause ends, but the display does not flash.

I point out the above to hopefully aid in producing a new bug-free rom by documenting all inconsistencies found with the current one.

edit - found another instance, changes in italics above.

Edited: 18 Nov 2011, 12:23 p.m. after one or more responses were posted

      
Re: 15c LE - Another Flashing Display Issue
Message #2 Posted by uhmgawa on 17 Nov 2011, 4:31 p.m.,
in response to message #1 by Jeff O.

Quote:
1. in complex mode...

2. in any mode, press f - PREFIX...


Sounds like another manifestation of the display controller winding up in buffer swap mode as was speculated here.

Quote:
I point out the above to hopefully aid in producing a new bug-free rom by documenting all inconsistencies found with the current one.

Just curious if an ETA was yet mentioned for a revised Owners Handbook?

      
Re: 15c LE - Another Flashing Display Issue
Message #3 Posted by Kiyoshi Akima on 17 Nov 2011, 4:42 p.m.,
in response to message #1 by Jeff O.

Apparently more differences between the 15C LE and the HHC2010 15C+. My HHC 15C+ exhibits neither of these behaviors. However, an overflowing operation leaves the display blank instead of blinking.

Interesting behavior I just came across: press EEX 2 g 10^x to cause an overflow and the display blanks. Press a digit key as if entering a new number and hold the key down. The display showing the new number blinks while the key is held down. Press and hold another digit key and the two-digit entry blinks while the key is held down.

Can someone else with the HHC 15C+ verify or dispute my results?

            
Re: 15c LE - Another Flashing Display Issue
Message #4 Posted by Jeff O. on 17 Nov 2011, 8:17 p.m.,
in response to message #3 by Kiyoshi Akima

Kiyoshi,
I think you are describing normal behavior (i.e. behavior exhibited by the original 15C), see this post.

Update - my 15C Classic behaves the same way, so not a new bug, just successful emulation of odd original behavior.

Edited: 18 Nov 2011, 3:08 p.m.


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