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Topic: using SRAM bus for UTFT ? (Read 1 time) previous topic - next topic

ralphnev

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 ....



ralphnev

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 !!

Graynomad

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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?

______
Rob
Rob Gray aka the GRAYnomad www.robgray.com

ralphnev

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  ..

Graynomad

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6" ribbon cable & things tended to get messy at 100ns

OK, that explains it.

______
Rob
Rob Gray aka the GRAYnomad www.robgray.com

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