interfacing rs 845 bus

[santoshganachar]

hi how  to interface lpc54114 to Rs 485 modbus device 

[kerryzhou]

Hi santosh Ganachari,

    Actually, RS485 is just need to control the RTS in the UART module.

    LPC54114 UART module already contains the LPC485 control function, you need to use the RTS connect the LPC485 send enable pin. Then the detail MODEBUS control, you just need to send the according UART data is OK.

   About the according register, please check this chapter in the user manual carefully.

Wish it helps you!

Have a great day,
Kerry

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[george]

Dear kerryzhou‌

Please let me do the question relevant to this post.

Is an RTS pin valid also in ISP mode?

Best Regards,

George

[kerryzhou]

Hi George,

   Unfortunately, in ISP mode, the UART just support UART_TX and UART_RX, no RTS is used, please check this information from the user mannual:

So, if you have the demand to use the RTS pin, maybe you need to create the secondary uart bootloader.

Wish it helps you!
Have a great day,
Kerry

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[george]

Dear Kerry,

Thank you for the kind explanation.

I see.

Thanks,

George

[kerryzhou]

You are welcome!

Next time, if you have the question, please create the question post by yourself,  we will help you directly in your own post.

Have a great day,
Kerry

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