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jecottrell
Joined: 16 Jan 2005 Posts: 559 Location: Tucson, AZ
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Help With Timing Diagram |
Posted: Sun Oct 09, 2005 5:18 pm |
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Tomorrow should bring a revised board for my latest on-going project. (Note to self: there is a difference between DIP and SDIP, pay attention next time.)
I am looking at the timing diagram on page 3 of the following datasheet:
http://www.marktechopto.com/PDFs/toshiba/TB62726AN-AF.pdf
Is there a typo or am I not understanding things correctly?
1. Serial data is read at the rising edge of the clock (I can't take credit for that one, someone else answered that for me on a previous post.)
2. A serial H will result in the corresponding LED to be OFF when latched and enabled, a serial L will result in the corresponding LED to be ON when latched and enabled. (?)
If that is correct, the timing diagram is showing a 1010101010101010 being read in, and even numbered LEDs would be OFF and odd numbered ON. HOWEVER, the timing diagram shows:
OUT0: OFF
OUT1: ON
OUT3: OFF (Wrong?)
OUT15: ON
Thanks,
John |
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jma_1
Joined: 08 Feb 2005 Posts: 147 Location: Wisconsin
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Posted: Mon Oct 10, 2005 6:54 am |
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Greetings,
I have never used this particular LED driver chip.
1) Yes
2) NO - ASCII H -> 1001000; L-> 1001100
(8 BITS ONLY)
Try sending 01010101 -> ASCII U (send 2 Times; each ASCII character only 8 bits). This should turn on even outputs and off odd LEDS
There appears to be a type-o in the datasheet OUT3 should be labeled OUT2
JMA |
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jecottrell
Joined: 16 Jan 2005 Posts: 559 Location: Tucson, AZ
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Posted: Mon Oct 10, 2005 8:03 am |
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Sorry, my explanation/question was confusing.
Quote: |
2. A serial H will result in the corresponding LED to be OFF when latched and enabled, a serial L will result in the corresponding LED to be ON when latched and enabled. (?)
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Would be more accurate/understandable if it read:
2. A serial High (or 1) when the clock is rising will result in the corresponding LED to be OFF when latched and enabled, a serial Low (or 0) when the clock is rising will result in the corresponding LED to be ON when latched and enabled. (?)
That is all I could figure, that it was a typo in the data sheet.
Thanks,
John |
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