i2c/SPI LCD Backpack

EL Wire/Tape/Panels, LEDs, pixels and strips, LCDs and TFTs, etc products from Adafruit

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afox
 
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Joined: Sat Aug 30, 2014 5:31 am

i2c/SPI LCD Backpack

Post by afox »

Hi all,

i am a bit confused about the usage of the board with hardware SPI pins.
In the guide is written "You can share the data and clock pins with another device as long as they remain outputs" but in the big red box "However, if you are using the hardware SPI port (such as for Ethernet, ...) you cannot share those pins with this LCD!".
Why cant i just use the default hardware SCK and MOSI pins from my micro?
Of course, the LATCH is a dedicated pin from the micro like CS in any default SPI case.


Thanks in advance!
Regards,
Alex

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afox
 
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Re: i2c/SPI LCD Backpack

Post by afox »

No answer / help for me? :(

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adafruit_support_mike
 
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Re: i2c/SPI LCD Backpack

Post by adafruit_support_mike »

The backpack doesn't have a CS pin, so it can't ignore signals to other devices using the hardware SPI pins. It's also difficult to get the timing for the LATCH pin right when you have other devices on the hardware SPI bus.

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