I2c Address Problem

nitin110051 · ‎2014-02-06

Posted on February 06, 2014 at 18:30

Dear Clive

i want to communicate two Board through is I2c

1. sTm32f103zg MB672

2. Stm32f103Rb Discovery board

for this i Need address Of both the Devices ,can you support me in matter how to found the Address of a device.

#stm32 #i2c #stm32 #i2c

Tesla DeLorean · ‎2014-02-06

Posted on February 06, 2014 at 19:03

I2C really isn't something I'm in to. If you control the code on both devices, you can surely define whatever 7-bit address you want to the slave device, and then use that to initiate the request in the master device?

STM3210E-EVAL (MB672) ?

You might want to review some of the samples

STM32F10x_StdPeriph_Lib_V3.5.0\Project\STM32F10x_StdPeriph_Examples\I2C\

There are probably other firmware examples demonstrating MASTER and SLAVE operation

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nitin110051 · ‎2014-02-06

Posted on February 07, 2014 at 05:09

Dear Clive,

Thank you For this Early Awnser

I looked at the example provided in St peripheral Library ,I saw that LM 75 is addressed From 0x90 (where it came from ?)

MB672 Is a Evaluation Board for Stm32F103ZG MCU .

Through MB672 i want to communicate with MB913C (evaluation board for Stm 32F103RB ).

Problem i am facing How to Determine what's the address of device

Tesla DeLorean · ‎2014-02-06

Posted on February 07, 2014 at 06:12

I saw that LM75 is addressed From 0x90 (where it came from ?)

It's implemented in the silicon of the part, and described in it's data sheet, page 5

http://datasheets.maximintegrated.com/en/ds/LM75.pdf

If you're using one of your STM32 as a SLAVE device YOU get to define the address, and program it into the ''SLAVE ADDRESS REGISTER'' when you configure the I2C interface

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nitin110051 · ‎2014-02-06

Posted on February 07, 2014 at 08:39

Dear Clive

Thank you For sharing this Details

But now i have one question in my mind If am using one stm32 as a slave and another stm32 as master ,to initiate transfer we need to provide address of slave in firmware of master's , for stm32f103zg what is the i2c address

Tesla DeLorean · ‎2014-02-07

Posted on February 07, 2014 at 15:29

#define MY_SLAVE_ADDRESS (0x30)

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