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I2C address beware

Topic last updated 01 Sep 2010, by Arthur P. Meiners. 1 reply
Liam Maskey
05 Jul 2010

I had problems connecting to an I2C eeprom whose address from the data sheet was given as 0x51. I used this address in the MBED code but the eeprom didn’t acknowledge this. Then I remembered that an I2C address is 7 bits long and for the address to be handled by the MBED code it needs to be shifted by 1 bit to the left  -  multiply by 2. So 0x51 becomes 0xA2 and the eeprom can now be addressed

Arthur P. Meiners
01 Sep 2010

Not so much a but as something to put in the documentation for the I2C class.