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Author Topic: using SRAM bus for UTFT ?  (Read 956 times)
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Ottawa,Canada
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Has anyone tried this ? (i'm digging into the internals  as it type ..)
just using a single address line & an 8bit bus ?

the reason behind this - i bought a 7" TFT 6 mo. ago & tried to attach it for the first time yesterday
--&  find out that 3 of the assigned data lines are dead on my DUE  (ya likely killed them with 5v , sigh ... )
so rather than reassign the bits why not use  External Memory Bus/Static Memory Controller http://forum.arduino.cc//index.php?topic=152644.msg1145789#msg1145789
should be faster right ??
bit of hacking up henning karlsen code but ....


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Ottawa,Canada
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this turned out to function quite well with single byte transfers on the order of 1/2 us
both reading & writing

it did take a bit of work to find the right parameters esp with this cheapo display
& trying to figure out some of the parameters of the ssd1963 .... 

but it works !!
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nr Bundaberg, Australia
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single byte transfers on the order of 1/2 us
Yikes that's slow, or is it determined by the display?

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Rob
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Rob Gray aka the GRAYnomad www.robgray.com

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I have not pushed it
  working with 6" ribbon cable & things tended to get messy at 100ns so i backed off
  ssd1963 claims to work at 50Mhz or faster (at least this one had a 50mz clock )
... but i doubt i get close with long wires  ..
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nr Bundaberg, Australia
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6" ribbon cable & things tended to get messy at 100ns
OK, that explains it.

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Rob
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Rob Gray aka the GRAYnomad www.robgray.com

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