MIMXRT1176CVM8A: Regarding Carrier detect pin of RS232 communication

[Deepak_India]

Hi Team,

The LPUART module of MIMXRT1176CVM8A has got TxD, RxD, CTS and RTS pins.

But however, our RS232 communication includes Carrier Detect (CD) pin as well.

Please let me know which pin to of Controller shall be used to connect to the CD pin of the RS232 Transceiver.

[Deepak_India]

Hi Pavel,

In our previous design, the controller MPC8270 had dedicated pin for Carrier Detect (CD) in UART module. However, as you are aware, the MIMXRT1176CVM8A has got TxD, RxD, CTS and RTS pins only and no CD pin.

We are retaining the RS232 Transceiver in the new design but changing the controller to MIMXRT1176CVM8A.

The RS232 Transceiver used is ISL83387EIVZ. And the Schematics part is as below:

Our thinking is that we can connect this MCU_0_CD net to UART's Receive pin since there is no CD pin. 

Can you please look into this and let us know your suggestion?

Regards

Deepak

[Pavel_Hernandez]

Hello, I try to find the datasheet of your device, but I could not find the DC.

Even if I change the datasheet for other, I could not find the pin, could you give the datasheet that you have?

I research more information on the web, and I suggest resolve this with a GPIO.

This signal is a simple "high/low" status bit that is sent from a data.
Its purpose varies depending on the device connected, but the most specific meaning is to indicate when a modem is connected to another remote modem via telephone lines.

Best regards,
Pavel

[Pavel_Hernandez]

Hello, my name is Pavel, and I will be supporting your case, I investigated the RS232 Carrier, but I did not find anything, maybe you need to use a GPIO to resolve this by software.

What is the Transceiver? maybe on the Datasheet, you will find more information.

Best regards,
Pavel

[Deepak_India]

Hi Pavel,

As of now, I have used a GPIO to connect the Carrier detect pin like you suggested.

Please find the datasheet of RS232 transciever in the below link.

https://www.renesas.com/us/en/document/dst/isl83387e-datasheet