CAN senden - STM32 F4

Ich versuche die CAN-Kommunikation für STM32F407IG sicherherzustellen, 
in dem Daten von CAN gesendet werden.
Mein Code enthält aber bestimmt eine Fehler, da die Überprüfung durch 
die Diodenbeleuchtung gescheitert ist.
kann mir evtl. jemand helfen die Fehler zu suchen ?
Wie kann man am besten die CAN-Kommunikation testen ?

Vielen Dank



Mein Code:

#include "stm32f4xx_rcc.h"
#include "stm32f4xx_gpio.h"
#include "stm32f4xx_can.h"
#include "misc.h"
#include "stm32f4xx.h"

           GPIO_InitTypeDef GPIO_InitStructure;
    CAN_InitTypeDef CAN_InitStructure;
              uint8_t Status = 0;
              uint8_t TransmitMailbox = 0;


void CAN_send (void)
{
SystemInit();
STM_EVAL_LEDInit();


 RCC_APB1PeriphClockCmd(RCC_APB1Periph_CAN1, ENABLE);

 RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOB, ENABLE);

 GPIO_InitStructure.GPIO_Pin = GPIO_Pin_8;
 GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;// Mode IPU (input) ?!
 GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
 GPIO_Init(GPIOB, &GPIO_InitStructure);

 GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9;
 GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
 GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
 GPIO_Init(GPIOB, &GPIO_InitStructure);

 GPIO_PinAFConfig(GPIOB, GPIO_PinSource8, GPIO_AF_CAN1);
 GPIO_PinAFConfig(GPIOB, GPIO_PinSource9, GPIO_AF_CAN1);

 CAN_InitStructure.CAN_Prescaler = 2;
 CAN_InitStructure.CAN_SJW = CAN_SJW_2tq;
 CAN_InitStructure.CAN_BS1 = CAN_BS1_11tq;
 CAN_InitStructure.CAN_BS2 = CAN_BS2_4tq;
 CAN_InitStructure.CAN_Mode = CAN_Mode_Normal;
 CAN_InitStructure.CAN_TTCM = DISABLE;
 CAN_InitStructure.CAN_ABOM = DISABLE;
 CAN_InitStructure.CAN_AWUM = DISABLE;
 CAN_InitStructure.CAN_NART = ENABLE;
 CAN_InitStructure.CAN_RFLM = DISABLE;
 CAN_InitStructure.CAN_TXFP = DISABLE;
 CAN_Init(CAN1, &CAN_InitStructure);

 /* CAN_Filter_int */
 CAN_FilterInitTypeDef CAN_FilterInitStructure;
 CAN_FilterInitStructure.CAN_FilterNumber = 0;
 CAN_FilterInitStructure.CAN_FilterMode = CAN_FilterMode_IdMask;
 CAN_FilterInitStructure.CAN_FilterScale = CAN_FilterScale_32bit;
 CAN_FilterInitStructure.CAN_FilterIdHigh = 0x0123 << 5;
 CAN_FilterInitStructure.CAN_FilterIdLow = 0x0000;
 CAN_FilterInitStructure.CAN_FilterMaskIdHigh = 0xFFFF;
 CAN_FilterInitStructure.CAN_FilterMaskIdLow = 0xFFFF;
 CAN_FilterInitStructure.CAN_FilterFIFOAssignment = 0;
 CAN_FilterInitStructure.CAN_FilterActivation = ENABLE;
 CAN_FilterInit(&CAN_FilterInitStructure);

/* CAN_Transmit */
  CanTxMsg TxMessage;
  TxMessage.StdId = 0x123;
  TxMessage.ExtId = 0;
  TxMessage.RTR = CAN_RTR_DATA;
  TxMessage.IDE = CAN_ID_STD;
  TxMessage.DLC = 8;
  TxMessage.Data[0] = 4;
  TxMessage.Data[1] = 4;

TransmitMailbox = CAN_Transmit(CANx, &TxMessage);
 Status= (CAN_TransmitStatus(CANx, TransmitMailbox);

if (Status == CAN_TxStatus_Ok)
    {STM_EVAL_LEDOn (LED1);
    }
    else
    STM_EVAL_LEDOn (LED2);

while(1)
{}
}