MSP430FR5969: MSP430 SMbus library bit shifting

Dmitry Kovalenkov

Part Number: MSP430FR5969
Other Parts Discussed in Thread: BQ40Z50,

Team,

One of my customers is using MSP430FR5969 with BQ40z50. the question is to why MSP430 SMbus library shifts the address when its sent, I have noticed that the is some bit shifting of the address to the left going on inside the SMBus library. Does anyone know why ?

Regards,

Dmitry

over 6 years ago

0 Gary Gao over 6 years ago

TI__Mastermind 37585 points

Hi Dmitry

You mean if you set the slave address to 0x01,but it sent 0x02 and can not get the ACK from the slave?

Best regards
Gary

0 Gary Gao over 6 years ago in reply to Gary Gao

TI__Mastermind 37585 points

Hi Dmitry

Have you solve the problem now?

0 Dmitry Kovalenkov over 6 years ago in reply to Gary Gao

TI__Intellectual 1210 points

Hi Gary,

That's what the customer would see if the address was 0x01 instead of 0x16.

it looks like the bit shifting is due to the address only having 7bits, with the last bit being a read/write bit. The address must be bit shifted to the left to make room for the read/write bit.

Does that sound correct?

Regards,

Dmitry

0 Gary Gao over 6 years ago in reply to Dmitry Kovalenkov

TI__Mastermind 37585 points

Hi Dmitry

For the 7bit addressing mode it's right.

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MSP430FR5969: MSP430 SMbus library bit shifting