MSP432P4011: UCSTPIFG getting set in master mode

Bhargava Gayathri

Part Number: MSP432P4011
Other Parts Discussed in Thread: SIMPLELINK-MSP432-SDK

Hello,

I am using the i2c drivers from SIMPLELINK-MSP432-SDK_2.30.00.14. I have a MSP432P4011 in master mode on the i2c bus continuously reading an i2c slave. I am seeing that the MSP in master mode is getting a UCSTPIFG. I also see that a call to the driver to write 1 byte is seen as 2 byte write on the bus when the UCSTPIFG bit is set on the master. You can see the scope capture below. There was a call to i2c master write to write 0x17. But, there are 2 0x17 that is seen on the scope.

What is the implication of UCSTPIFG in master mode and how do I go about handling it in master mode?

Thanks,

Bhargav

over 5 years ago

0 Leonardo Estevez over 5 years ago

TI__Genius 12615 points

Hi Bhargava,

You can learn more about this flag in Section 26.3.10.4 I 2C State Change Interrupt Operation of the technical reference document:

http://www.ti.com/lit/ug/slau356i/slau356i.pdf

You can also find some code examples on how I2C is used in master mode here:

https://dev.ti.com/tirex/explore/node?node=ADoDWIZc5WTuUbxxkAgevQ__z-lQYNj__LATEST

BR,
Leo

0 Bhargava Gayathri over 5 years ago in reply to Leonardo Estevez

Prodigy 20 points

Hi Leo,

Thank you for the links. I have checked the driver code of Simplelink library and it does not handle Stop interrupt in master mode. I am using version 2.30. Does upgrading to a newer version fix this?

Thanks,

Bhargav

0 Leonardo Estevez over 5 years ago in reply to Bhargava Gayathri

TI__Genius 12615 points

Hi Bhargava,

Are you looking at example code from the resource explorer link I provided? I recommend that you try this code in your application to determine whether it might work without modification. Please note that there is a single interrupt used to service multiple interrupt flags.

BR,
Leo

Arm-based microcontrollers

Arm-based microcontrollers forum

MSP432P4011: UCSTPIFG getting set in master mode