MC9S08PT8VLC - Setting Baud rate to 9600

[amitmallick]

Hi NXP Support,

We are using the freescale microcontroller MC9S08PT8VLC to communicate with a Zigbee network. The communication with Zigbee is possible at 9600 baud rate. Could you please assist us on how we can set the baud rate of the chip. Below is a snippet of the code we are using to flash the MC. 

void PC_UART_Init(void)
{
SYS_SOPT2 &= (byte)(~(byte)(0x80U));

PORT_PTCOE = PORT_PTCOE & ((byte)(~(byte)(0x40U))) | (byte)(0x80U);
PORT_PTCIE = PORT_PTCIE & ((byte)(~(byte)(0x80U))) | (byte)(0x40U);
PORT_PTCD |= (byte)(0x80U);

SCI1_C1 = (byte)(0x00U);
SCI1_C3 = (byte)(0x00U);
SCI1_C2 = (byte)(0x00U);
SCI1_S2 = (byte)(0x00U);
#ifdef INTERNAL_CLOCK
SCI0_BDH = 0x00U;
SCI0_BDL =0xC3U; //9600
#endif
#ifdef EXTERNAL_CLOCK
SCI0_BDH = 0x00U;
SCI0_BDL = 0x34U; //9600
#endif

Please assist us how can we reset the baud rate of MC to 9600. Let us know in case you need any other information.

[ZhangJennie]

Hi.

if use 31.25k internal clock,The FLL loop locks the frequency to the 512 times the internal reference frequency.

with FEI mode, FLL output = 31.25k*512=16MHz

BUSCLOCK= FLL output/BDIV= 16/1=16M, here BDIV is bus frequency divide

SCI baud rate = BUSCLOCK/SCIBD/16=16M/104/16=9615

(SCIBDL=0x68 which decimal number is 104)

Have a great day,
Jennie Zhang

-----------------------------------------------------------------------------------------------------------------------
Note: If this post answers your question, please click the Correct Answer button. Thank you!
-----------------------------------------------------------------------------------------------------------------------