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i am trying to interface a cheap LCD panel to BBB so basically i am making my own LCD7 cape but without the EPROM & I2C stuff and till now i have succesfully wrote a device tree overlay , loaded it, and fried a LCD panel well ...without any smoke.

the problem is after checking the LCD7 made by circuitco i noted this IC between the beagle and the LCD : 74AVC32T245

i dont really understand why its there here is the opensource design of LCD7 cape the transducer is at page 21

http://www.openhacks.com/uploadsproductos/beaglebone-lcd7-reva2-srm.pdf

any help regarding out to interface LCD panels is very appresiated

MolhamStein
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  • I have been working on a similar issue. Look at following post. Hopefully they will help you. http://stackoverflow.com/questions/20975014/how-to-change-device-lcd-parameters-dynamically-on-android-linux-arm-device – Mahendra Gunawardena Jan 07 '14 at 16:37
  • thanks for your interest i think this post may be important for me in later stages but for now my problem is regarding the hardware design of the LCD interface – MolhamStein Jan 08 '14 at 00:49

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on page 20 of that document, section 5.2.2: Non-Inverting Bus Transceiver explains everything. The chip is meant for voltage level translation, just in case the LCD and the MCU operate at different levels. But in the BeagleBone LCD7 Cape, no translation is required. So its just a buffer, I don't think it should matter in the code implementation. It does say "its two power rails are both 3.3V" So you should observe that.

Karibe
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