topic I2C_LDD 10 bit addressing in Kinetis Microcontrollers

I2C_LDD 10 bit addressing

richardfox75 — Wed, 01 Jun 2016 12:13:05 GMT

The micro that I am using is an MK22FN256LVQ, there is a 24C16 EEPROM connected to I2C CH0.

A logic analyzer is monitoring the SCL and SDA lines. Attempting to address an EEPROM address

of 0x15B. Issuing the dummy write to load the 10 bit address into the EEPROM shows a byte of

0s before the 10 bit address code, 11110XX. I am using the most recent version of the Processor

Expert I2C component, the I2C_LDD.

Any ideas why the 0s byte? This results in my access being NACked.

Re: I2C_LDD 10 bit addressing

Hui_Ma — Thu, 02 Jun 2016 08:44:29 GMT

I checked the 24C16 datasheet, during the device select phase, there with below device code:

While the K22 I2C module 10-bit address mode with below description, the 0b11110 is used for first 5 bits of the first address byte.

I don't think it is suitable to use I2C 10-bit address mode when communication with 24C16 EEPROM.

Customer still need to using the 7-bit address, which simulate the 24C16 device select phase, such as:

AD[7:1] = 0b1010XXX

After that using one byte data as low 8-bit address (BYTE ADDR).
Wish it helps.

Have a great day,
Ma Hui
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Re: I2C_LDD 10 bit addressing

richardfox75 — Thu, 02 Jun 2016 13:21:49 GMT

Hello,

Yes you are correct, the 24C16, cannot be used as a 10 bit address device.

It is a 7 bit device with 8 blocks.

I found this out shortly after my post. Sorry, for the waste of your time.

Regards,

Dick Fox

Firmware Engineer

NATIONAL CONTROLS CORPORATION BUSINESS UNIT

INSTRUMENTATION AND SPECIALTY CONTROLS DIVISION

1725 Western Dr | West Chicago, IL 60185 | http://www.ametekncc.com

Phone: (630)621-3118 | email: Dick Fox@ametek.com