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    can I use 5V for TFT LCD ?

    Hello Guys,

    Can I connect directly 5V output port from AT89C55WD into ILI9325 TFT ?
    I want to connect P0 and P2 into DB0-DB15, is it possible ?

    thanks

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    Re: can I use 5V for TFT LCD ?

    It is written in spec it is 2.4V-3.3V.
    See spec page12
    http://www.adafruit.com/datasheets/ILI9325.pdf



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    Re: can I use 5V for TFT LCD ?

    Quote Originally Posted by emresel View Post
    It is written in spec it is 2.4V-3.3V.
    See spec page12
    http://www.adafruit.com/datasheets/ILI9325.pdf
    Do you have example for init code and displaying pant ?
    In C and for MCS51 ?

    Thanks



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    Re: can I use 5V for TFT LCD ?

    sorry, unfortunately not:(
    Just check the datasheet to help.

    Good luck



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    Re: can I use 5V for TFT LCD ?

    For level conversion you may use some logic 7400 family chips, which operate from 3V3 but have 5V tolerant inputs. Otherwise you may use resistor and zener diode for each individual signal line. This is for one direction communication from mcu to lcd. For bidirectional level translation u may use something like this Voltage Level Translation - Dual Supply Translator - SN74LVC4245A - TI.com



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    Re: can I use 5V for TFT LCD ?

    Quote Originally Posted by poorchava View Post
    For level conversion you may use some logic 7400 family chips, which operate from 3V3 but have 5V tolerant inputs. Otherwise you may use resistor and zener diode for each individual signal line. This is for one direction communication from mcu to lcd. For bidirectional level translation u may use something like this Voltage Level Translation - Dual Supply Translator - SN74LVC4245A - TI.com
    very valuable information, thanks a lot mate

    ---------- Post added at 12:20 ---------- Previous post was at 11:39 ----------

    I had better use AT89LV55 to resolve this matter, and simplify the circuit too....but thanks for the info guys



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    Re: can I use 5V for TFT LCD ?

    You can also use simple resistor dividers to convert 5V to 3.3V. But this is (same for drivers above) only unidirectional.
    For bidirectional communication I'd really suggest to use a 3.3V 8051. Not hard to find.
    Maybe you want to read registers or memory from TFT, e.g. for modifying the picture? Internal memory in TFTs is very big and you can't keep a shadow copy in MCU RAM...



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    Re: can I use 5V for TFT LCD ?

    Quote Originally Posted by M!k View Post
    You can also use simple resistor dividers to convert 5V to 3.3V. But this is (same for drivers above) only unidirectional.
    For bidirectional communication I'd really suggest to use a 3.3V 8051. Not hard to find.
    Maybe you want to read registers or memory from TFT, e.g. for modifying the picture? Internal memory in TFTs is very big and you can't keep a shadow copy in MCU RAM...
    Do you have a link for TFT Init code?

    Thanks[COLOR="Silver"]



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    Re: can I use 5V for TFT LCD ?

    Quote Originally Posted by bianchi77 View Post
    Do you have a link for TFT Init code?

    Thanks
    No, but how about asking Google: Arduino Forum - Arduino control the 2.4" TFT LCD



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    Re: can I use 5V for TFT LCD ?

    Quote Originally Posted by M!k View Post
    No, but how about asking Google: Arduino Forum - Arduino control the 2.4" TFT LCD
    How can I translate Arduino code for MCS51 ?

    I can not see digital_write function in that code.
    Are there any clues for it ?



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