Multiplexed Display
MR
Posts: 46
I am multiplexing 10 seven segment displays and 3 14 segment displays.
The display appears solid but I can still see visible flicker. The displays are "bouncing".
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If it Stinks it is Chemistry
If it Gooey its Biology
If it doesn't work its Physics
They say if you Play a Microsoft CD backwards you can hear satanic messages, that's nothing because if you play it forward it installs Vista!
I didn't Fail 10,000 times, I simply found 10,000 ways that didn't work. -Thomas Edison
640 KB is all the memory anyone will ever need. -Bill Gates in a 1980's interview talking about Windows.
In 1969, the crew of Apollo 11 landed on the moon. A standard calculator has more computing power than the Apollo 11 computer, yet it takes almost 3 Gigs to Run Vista. Something is wrong here!
The display appears solid but I can still see visible flicker. The displays are "bouncing".
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If it Stinks it is Chemistry
If it Gooey its Biology
If it doesn't work its Physics
They say if you Play a Microsoft CD backwards you can hear satanic messages, that's nothing because if you play it forward it installs Vista!
I didn't Fail 10,000 times, I simply found 10,000 ways that didn't work. -Thomas Edison
640 KB is all the memory anyone will ever need. -Bill Gates in a 1980's interview talking about Windows.
In 1969, the crew of Apollo 11 landed on the moon. A standard calculator has more computing power than the Apollo 11 computer, yet it takes almost 3 Gigs to Run Vista. Something is wrong here!
1024 x 1280 - 44K
1024 x 1280 - 48K
Comments
The displays have flicker and I wanted to know how to get rid of the flicker?
Here is a video link
Thanks.
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If it Stinks it is Chemistry
If it Gooey its Biology
If it doesn't work its Physics
They say if you Play a Microsoft CD backwards you can hear satanic messages, that's nothing because if you play it forward it installs Vista!
I didn't Fail 10,000 times, I simply found 10,000 ways that didn't work. -Thomas Edison
640 KB is all the memory anyone will ever need. -Bill Gates in a 1980's interview talking about Windows.
In 1969, the crew of Apollo 11 landed on the moon. A standard calculator has more computing power than the Apollo 11 computer, yet it takes almost 3 Gigs to Run Vista. Something is wrong here!
Post Edited (MR) : 3/27/2009 3:16:35 AM GMT
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- Stephen
Nice job. Franklin is correct. You're not updating it often enough. I glanced at your code and my first impression is that you're trying to do a lot and there's not enough time to do it all. You need to refresh the display at least 60 times a second to avoid noticible flicker, that's roughly once every 16ms. A SHIFTOUT takes maybe 300us. A very simple statement like HIGH or LOW takes maybe 40us. Your main cycle takes on the order of 50 SHIFTOUTs, that's well over 15ms right there. You've got a lot of "PAUSE hold" statements and I'm not sure how they're interpreted. "hold" is set to zero (1/500), so the pause may be quite short. Without comments and without a schematic, I wouldn't begin to advise you on how to fix this up other than that the main cycle has to be more efficient and faster.
The SHIFTOUT command can transmit more than 8 bits at a time and you·can use this feature to improve the efficiency of the SHIFTOUT command. Since PBASIC·is an interpreted language, each command is interpreted and then executed;·the execution time to send the bits in the SHIFTOUT·command·is pretty short.·Combining SHIFTOUT commands, where appropriate, can reduce the overhead associated with the interpretation.
As an example, you have the following lines of code when you are writing to the LOWNIB of the variable [noparse][[/noparse]minutes]:
DIRD=minutes.HIGHNIB
SHIFTOUT SerData, Clock, MSBFIRST, [noparse][[/noparse]%11111110] ' send counter to 595-2
SHIFTOUT SerData, Clock, MSBFIRST, [noparse][[/noparse]%11111111] ' send pattern to 595-1
PULSOUT Latch, HoldL ' latch outputs
PAUSE hold
GOSUB clear
You can combine the two SHIFTOUT commands in this example as follows:
SHIFTOUT SerData, Clock, MSBFIRST, [noparse][[/noparse]%11111110,%11111111].
The YouTube video is impressive.
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························ Craig Eid
··········· Triad Research and Development
Electical Engineering Design and Consulting Services
··················· www.TriadRD.com
Thanks.
How do I change the mode from 24 hour to 12 hour clock? Please use the code that I uploaded.
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They say if you Play a Microsoft CD backwards you can hear satanic messages, that's nothing because if you play it forward it installs Vista!
I didn't Fail 10,000 times, I simply found 10,000 ways that didn't work. -Thomas Edison