UART help on K60 TWR?

[plewis]

I am trying to get a simple UART application to work in MQX 4.1 (CodeWarrior) on a TWR K60F120M kit.  I have 2 tasks opening 2 different UARTS, one is writing and one is reading.  I am using UART4 to write and UART2 to read.  On the TWR headers, I have placed a wire to jumper between B80 (UART4 write pin) and A76 (UART2 read pin).  I am using the fopen(), fread(), and fwrite() functions.  I am using the interrupt-enabled drivers by opening the ports with ittyc and ittye.

This should be a very simple operation, but I cannot get it to work.  Can anyone help me here?  Am I using the wrong functions? Am I not setting up something properly here?

Here is the console output I receive from this from the printf() calls:

UART2 task started

UART4 task started

UART2:  0 1 2 3 4 5 6 7 8 9 10 10 11 12 10 14 15 16 17 18 20 21 22 23 24 25 26 27 28 29 30 31

UART2:  32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63

UART2:  64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 18 20 21 22 23 24 25 26 27 28 29

UART2:  30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61

Since I am sending a ramp pattern continuously, I expect to receive that without breaks in the data, and not repeated values, regardless of the starting value that I receive.

Here is the source code:

//*****************************************************************************

//*****************************************************************************

// main.c

//*****************************************************************************

//*****************************************************************************

#include <mqx.h>

#include <bsp.h>

#include <fio.h>

#include <timer.h>

#include <serial.h>

#if ! BSPCFG_ENABLE_IO_SUBSYSTEM

#error This application requires BSPCFG_ENABLE_IO_SUBSYSTEM defined non-zero in user_config.h. Please recompile BSP with this option.

#endif

#ifndef BSP_DEFAULT_IO_CHANNEL_DEFINED

#error This application requires BSP_DEFAULT_IO_CHANNEL to be not NULL. Please set corresponding BSPCFG_ENABLE_TTYx to non-zero in user_config.h and recompile BSP with this option.

#endif

// Task IDs

#define UART2_TASK  7

#define UART4_TASK  8

extern void uart2_task(uint32_t);

extern void uart4_task(uint32_t);

const TASK_TEMPLATE_STRUCT  MQX_template_list[] =

{

   // Task Index,   Function,     Stack,  Priority, Name,      Attributes,          Param, Time Slice

    { UART2_TASK,   uart2_task, 1000,   7,          "uart2",   MQX_AUTO_START_TASK, 0,     0 },

    { UART4_TASK,   uart4_task, 1000,   8,          "uart4",   MQX_AUTO_START_TASK, 0,     0 },

    { 0 }

};

FILE_PTR uart2_serial_device;

FILE_PTR uart4_serial_device;

uint8_t write_buf[128] = {0};

uint8_t read_buf1[32]  = {0};

uint8_t read_buf2[32]  = {0};

uint8_t read_buf3[32]  = {0};

uint8_t read_buf4[32]  = {0};

//-----------------------------------------------------------

// UART2

// Port assignment:  UART2 Tx = PTD3; UART2 Rx = PTD2

// TWR header pins:  UART2 Tx = A77;  UART4 Rx = A76

//-----------------------------------------------------------

void uart2_task(uint32_t initial_data)

{

   int i;

   printf("UART2 task started\n");

   // Configure PTD2 & PTD3 for ALT3 function

   PORTD_PCR2 = PORT_PCR_MUX(3);

   PORTD_PCR3 = PORT_PCR_MUX(3);

   uart2_serial_device = fopen("ittyc:", BSP_DEFAULT_IO_OPEN_MODE);

   fread(&read_buf1[0], 1, 32, uart2_serial_device);

   fread(&read_buf2[0], 1, 32, uart2_serial_device);

   fread(&read_buf3[0], 1, 32, uart2_serial_device);

   fread(&read_buf4[0], 1, 32, uart2_serial_device);

   printf("UART2:  ");

   for (i=0; i<32; i++)

     printf("%d ", read_buf1[i]);

   printf("\n");

   printf("UART2:  ");

   for (i=0; i<32; i++)

     printf("%d ", read_buf2[i]);

   printf("\n");

   printf("UART2:  ");

   for (i=0; i<32; i++)

     printf("%d ", read_buf3[i]);

   printf("\n");

   printf("UART2:  ");

   for (i=0; i<32; i++)

     printf("%d ", read_buf4[i]);

   printf("\n");

   fclose(uart2_serial_device);

   _task_block();

}

//-----------------------------------------------------------

// UART4

// Port assignment:  UART4 Tx = PTC15; UART4 Rx = PTC14

// TWR header pins:  UART4 Tx = B80;   UART4 Rx = B79

//-----------------------------------------------------------

void uart4_task(uint32_t initial_data)

{

   int i;

   printf("UART4 task started\n");

   for (i=0; i<128; i++)

     write_buf[i] = (i & 0xFF);

   // Configure PTC14 & PTC15 for ALT3 function

   PORTC_PCR14 = PORT_PCR_MUX(3);

   PORTC_PCR15 = PORT_PCR_MUX(3);

   PORTE_PCR24 = PORT_PCR_MUX(0);        //Disable default UART4_TX

   PORTE_PCR25 = PORT_PCR_MUX(0);        //Disable default UART4_RX

   uart4_serial_device = fopen("ittye:", BSP_DEFAULT_IO_OPEN_MODE);

   while(1)

   {

      fwrite(&write_buf[0], 1, 128, uart4_serial_device);

   }

   fclose(uart4_serial_device);

   _task_block();

}

/* EOF */

[plewis · Accepted solution]

I figured out how to get this to work.  All I had to change was the value for the second field in the fopen() calls.  Where they had been:

uart2_serial_device = fopen("ittyc:", BSP_DEFAULT_IO_OPEN_MODE);

and

uart4_serial_device = fopen("ittye:", BSP_DEFAULT_IO_OPEN_MODE);

are now:

uart2_serial_device = fopen("ittyc:", NULL);

and

uart4_serial_device = fopen("ittye:", NULL);

Looking further into it, BSP_DEFAULT_IO_OPEN_MODE is defined in Freescale_MQX_4_1\mqx\source\bsp\twrk60f120m\twrk60f120m.h as:

#define BSP_DEFAULT_IO_OPEN_MODE (void *) (IO_SERIAL_XON_XOFF | IO_SERIAL_TRANSLATION | IO_SERIAL_ECHO)

These are 3 options that I do not want.

Another thing that needs changing is the defined task priorities.  In one of the MQX user guides I found that user tasks should be given priorities above 8.  With these changes, I now get the console output that I expect:

UART2 task started

UART4 task started

UART2:  0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31

UART2:  32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63

UART2:  64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95

UART2:  96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127