MPC5607B UART Baudrate Issue

[rehan_khan]

Hi,

We are using MPC5607B  for our development. We are trying to use the LINFlex in UART  mode. Following are the settings in our code.

void LOP_CH1_LIN3_Init(void)

{

  LINFLEX_3.LINCR1.B.INIT = 1;

  LINFLEX_3.LINCR1.B.SLEEP = 0;

  LINFLEX_3.LINIBRR.R = 0x00000005;       //baud rate 781250b/s (fsys 64MHz)

  LINFLEX_3.LINFBRR.R = 0x00000002;

  LINFLEX_3.UARTCR.B.UART = 1;

  LINFLEX_3.UARTCR.R  = 0x00002423;   

  LINFLEX_3.LINIER.B.DRIE = 1;                   //Receive interrupt enable

  LINFLEX_3.LINCR1.B.INIT = 0;                   //disable init mode

  SIU.PCR[8].R = 0x0100;

  SIU.PSMI[31].R = 0;

}

We are sending data at 781250 baudrate. At this baudarte UART module doesn't get interrupt. The max baudrate at which UART can enter into ISR is 115200. How can we increase the maximum UART baud rate capacity of the controller.

Is 115200 the maximum baudarte that can be handled by MPC5607B controller.

[martin_kovar]

Hi,

I tested your code on XPC56XX EVB motherboard and XPC560B 176LQFP minimodule with micro SPC5607B mask set 1M03Y. I connected microcontroller with PC. I sent characters from Putty to micro and interrupt worked correct.

I also tested baud rates 115200b/s, 230400b/s, 460800b/s and 921600b/s and all of these ones also worked correct.

Do you use NXP EVB or have you your own design board?

Regards,

Martin

[rehan_khan]

Hello,

I did the same thing from PC to check the code at different baudrates and its working fine. The problem is, we have another small board which connects to this MPC5607B on UART and sends the data at 786520 baud rate. When we send the data using this small board UART, it doesn't interrupt the 5607B controller. Following are the connection between 5607B and our small board.

5607B-------RS232-----RS485-----RS232----OTHER-Controller

Regards.

[martin_kovar]

Hi,

from your last post it seems, there is a problem with your "small board" or RS232/RS485 conversion. We both verified, that microcontroller works correct. So you should measure the signal from your board and also measure the signal after conversion from rs485 to rs232. Check, if there are correct voltage levels and also timing parameters.

Regards,

Martin

[rehan_khan]

We have just verified that our small board is not behaving properly. As soon as we connect the small board the voltage at the small board drops down. When we gave external voltage source It went into the ISR routine of the UART