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[SOLVED] i2c pullup resistor and spi

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dxtr

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hey everyone
i'm trying to connect 2 devices with my pic 18f2550 , one of them uses spi and the other uses i2c
the i2c bus needs pullup resistor , are they going to have any influence on the spi knowing that they have 2 pins in common ?
 

I don't know the answer, but what about powering the pull-up resistor from another PIC output? To turn it off, just set the pin to input so it is high impedance.
 

Unfortunately, you cannot attach an I2C and SPI device to the same peripheral hardware module and access them at the same time.

You can implement a software I2C interface and attach the SPI device to the hardware module.

I believe MikroC Libraries offer a software I2C library routine.

MikroC Software I²C Library


BigDog
 

Hi dxtr;

In my experience, it is possible, but of course not at the same time. The two pullup does not interfere with the SPI.
But I do not use the compiler built-in routines (SPI and I2C libraries), just the ones I wrote.
zuisti
 

what about the uart module , rx and sdo are in the same pin
also i can't use uart with spi ?
 

dxtr said:
what about the uart module , rx and sdo are in the same pin
also i can't use uart with spi ?
Click to expand...

What I wrote above, is still valid. The cleared SSPEN bit releases all the SPI bits and free to be used for any other purposes (eg RX).
 
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    dxtr

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zuisti said:
What I wrote above, is still valid. The cleared SSPEN bit releases all the SPI bits and free to be used for any other purposes (eg RX).
Click to expand...
its a very goood news thank you so much
 

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