MSP430FR5889: Technical issues

Zhonghui Xu

Part Number: MSP430FR5889

Hi team,

I got a question from customer.

"As I have been writing regarding the issues in PORT1, where one pin9 (port 9.0)designated as analog input, while other 7 pins as DIGITAL OUTPUT,the ADC reading is going wrong. The ADC READING GOES WRONG when communication in PORT 4(PORT 4.2Tx&4.3Rx ) is initiated.All the power supplies are isolated at the source itself with only ONE POINT INTERCONNECTION as needed.The communication port is driving RS485 through an ISOLATED POWER SUPPLY and the digital isolator (MAX14932 DAWE+)drawing very small current .wHEN THIS IS SWITCHED off ADC READING becomes normal.."

MSP430FR5889IPM_MODIFIED DESIGN.pdf MSP430FR5889IPM_OLD DESIGN.pdf

Thank you very much for your help.

Best regards,

over 3 years ago

0 Cash Hao11 over 3 years ago

TI__Mastermind 39235 points

Hi,

There are two design files in this thread. In the old one, P1.2 is the DIR_485_mc and P9.0 is the analog input. In the new one, P1.2 is the analog input and P9.0 is the DIR_485_mc. I want to check in which design you get the ADC wrong, or in both design the ADC will goes wrong.

Best regards,

Cash Hao

0 CHANDRA SEKARAN VT over 3 years ago

Prodigy 235 points

In both the ADC went wrong.As I had indicated many products with MSP430FR5889 work without any problems. But in this design, due to a an introduction of 128X1228 ;LCD DISPLAY, we were forced to use one analog input while the rest were allocated to digital output.

What I able to see if see is the VOLTAGE DROP ACROSS THE SERIES RESISTANCE FEEDING THE ADC INPUT SEES VARYING VOLTAGE INDICATING THAT WHILE ADC IS PEFFORMING,IT APPEARS THE OUTPUT SWITCHED ON OTHER PINS IN THE SAME PORT PUSUES SOME VOLTAGE TO THIS ADC INPUT.

IF WE DONOT CHANGE THE DIGITAL OUTPUT, THE ADC FREADING DOES NOT CHA NGE.

0 Zhonghui Xu over 3 years ago in reply to Cash Hao11

TI__Expert 5445 points

Hi Hao,

Thank you for your help.

Chandra Sekaran VT is the end user. You can communicate with him directly.

If you need some information to solve the problem, you can ask him to provide it directly.

Thanks again.

Best regards,

0 CHANDRA SEKARAN VT over 3 years ago in reply to Zhonghui Xu

Prodigy 235 points

i am not getting any reply from Mr.Hao.Can I get his email id.There appears to be some issues with this site

0 CHANDRA SEKARAN VT over 3 years ago in reply to CHANDRA SEKARAN VT

Prodigy 235 points

i am not getting any reply from Mr.Hao.Can I get his email id.There appears to be some issues with this site

0 Cash Hao11 over 3 years ago in reply to CHANDRA SEKARAN VT

TI__Mastermind 39235 points

Hi,

Sorry for the late response. My email address is cash-hao@ti.com. You can send out your issues through the email.

Best regards,

Cash Hao

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MSP430FR5889: Technical issues