23LC1024 pull up resistor ?

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bianchi77
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Posted by bianchi77: Sat. Sep 19, 2015 - 04:00 AM
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Guys,

 

Do I need a pull up resistor for MOSI,MISO,SCK and CS for 23LC1024 ?

Thanks

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AVR Microcontrollers, megaAVR and tinyAVR
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Kartman
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Posted by Kartman: Sat. Sep 19, 2015 - 04:43 AM
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A 10k pullup on miso might e beneficial, but why do you think you need pullups on spi? With i2c, pullups are mandatory otherwise it won't work.

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bianchi77
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Posted by bianchi77: Sat. Sep 19, 2015 - 08:48 PM
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I see, because SPI is a serial communication too...just in case it's not stable.....I2C it's a serial as well.....and why it's  mandatory for I2C and it's not with SPI ?

I put all pull ups  for my SDcard......MOSI,MISO,SCK,CS.....

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Bronze Markjs
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Posted by js: Sat. Sep 19, 2015 - 09:23 PM
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why it's  mandatory for I2C

Because I2C uses "open  collector" drivers ie they can only pull down the communication lines so you need resistors to pull the lines high.

 

SPI, USART and others drive the line high and low.

John Samperi

Ampertronics Pty. Ltd.

https://www.ampertronics.com.au

* Electronic Design * Custom Products * Contract Assembly

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bianchi77
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Posted by bianchi77: Sat. Sep 19, 2015 - 09:35 PM
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Ok John, Open collector output.....I see, thanks....

Can I use the code from 23K256 for 23LC1024?

from the datasheet I read, they have similarity, only different on capacity ( addressing )...

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