UART and PLM ST7540 on cortexM0

[pietro2]

Posted on March 20, 2013 at 16:53

Hi guys,i'm learning about the st7540 PLM device.

My hardware configuration is the seguent:STM32F0Discovery board and two EVALST7540-2 (st7540 transceiver).Microcontroller--->St7540transceiver--->220V--->St7540tranceiver--->scope.I've got an EVALCOMMBOARD too (sending with it i see the bytes on the scope correctly).My target is to send something via UART from microcontroller an see it on the scope at the end of the communication chain.I've read that st7540 default configuration is like that: asynchronous communication without a protocol. Reading datasheet seems that simply connecting an UART device to the transceiver, and it (the transceiver) provide the communication on 220 channel.I've connected the sending transcinver in this way (asynchronous sending):UART/SPI pin= 3vRXTX, GND, REGDATA = gndTXD= PA9 pinand the receiving transceiver in this way (asynchronous receiving):UART/SPI, RXTX= 3vGND, REGDATA = gndRXD= SCOPEi use a very simple code :/* Includes ------------------------------------------------------------------*/&sharpinclude ''stm32f0xx.h''&sharpinclude ''stm32f0_discovery.h''&sharpinclude ''stdio.h'' &sharpinclude <string.h>/** @addtogroup STM32F10x_StdPeriph_Examples  * @{  *//** @addtogroup USART_Polling  * @{  */ /* Private typedef -----------------------------------------------------------*/typedef enum { FAILED = 0, PASSED = !FAILED} TestStatus;/* Private define ------------------------------------------------------------*/&sharpdefine TxBufferSize   (countof(TxBuffer))/* Private macro -------------------------------------------------------------*/&sharpdefine countof(a)   (sizeof(a) / sizeof(*(a)))/* Private variables ---------------------------------------------------------*/USART_InitTypeDef USART_InitStructure;uint8_t TxBuffer[] = ''Buffer Send from USARTy to USARTz using Flags'';uint8_t RxBuffer[TxBufferSize];__IO uint8_t TxCounter = 0, RxCounter = 0;  volatile TestStatus TransferStatus = FAILED;  /* Private function prototypes -----------------------------------------------*/TestStatus Buffercmp(uint8_t* pBuffer1, uint8_t* pBuffer2, uint16_t BufferLength);__IO uint8_t index = 0;  /* Private functions ---------------------------------------------------------*/void USART_Configuration(void);void USART2_Configuration(void);GPIO_InitTypeDef    GPIO_InitStructure; /**  * @brief  Main program  * @param  None  * @retval None  */int main(void){  /*!< At this stage the microcontroller clock setting is already configured,        this is done through SystemInit() function which is called from startup       file (startup_stm32f10x_xx.s) before to branch to application main.       To reconfigure the default setting of SystemInit() function, refer to       system_stm32f10x.c file     */             USART_Configuration();    while (1)  {         while(TxCounter < TxBufferSize)  {       /* Send one byte from USART1 */    USART_SendData(USART1, TxBuffer[TxCounter++]);      /* Loop until USART1 DR register is empty */     while(USART_GetFlagStatus(USART1, USART_FLAG_TXE) == RESET)    {    }        /* Loop until the USARTz Receive Data Register is not empty */      }   TxCounter=0;    }}/**  * @brief Configura l'USART   * @param  None  * @retval None  */ void USART_Configuration(void){     /* Abilita clock GPIOA e DMA  */  RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOA , ENABLE);    /* Abilita clock USART1 APB  */  RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1, ENABLE);    NVIC_InitTypeDef NVIC_InitStructure;    /* configurazione pin USART1   **************************************************/ // GPIO_DeInit(GPIOA);    /* Connette i pin PA9 e PA10 alla periferica USART */  GPIO_PinAFConfig(GPIOA, GPIO_PinSource9, GPIO_AF_1);      GPIO_PinAFConfig(GPIOA, GPIO_PinSource10, GPIO_AF_1);     /* Configura i pin come AF pushpull */  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9 | GPIO_Pin_10 ;  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_Level_2;  GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;  GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;  GPIO_Init(GPIOA, &GPIO_InitStructure);     /* Configurazione USART1:  - BaudRate = 115200 baud    - Word Length = 8 Bits  - Stop Bit = 1 Stop Bit  - Parity = No Parity  - Hardware flow control disabled (RTS and CTS signals)  - Receive and transmit enabled  */     USART_DeInit(USART1);  USART_InitStructure.USART_BaudRate = 4800;  USART_InitStructure.USART_WordLength = USART_WordLength_8b;  USART_InitStructure.USART_StopBits = USART_StopBits_1;  USART_InitStructure.USART_Parity = USART_Parity_No;  USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;  USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;  USART_Init(USART1, &USART_InitStructure);  USART_ITConfig(USART1, USART_IT_RXNE, ENABLE); // enable the USART2 receive interrupt         NVIC_InitStructure.NVIC_IRQChannel = USART1_IRQn;                // we want to configure the USART2 interrupts        NVIC_InitStructure.NVIC_IRQChannelPriority = 0;// this sets the priority group of the USART2 interrupts        NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;                  // the USART2 interrupts are globally enabled        NVIC_Init(&NVIC_InitStructure);              USART_Cmd(USART1, ENABLE); }CAN SOMEONE HELP ME, PLEASE ??? #plm-via-uart-asynchronous-config

[Tesla DeLorean]

Posted on March 20, 2013 at 17:13

Code doesn't look offensive.

What's NOT happening? Can you see the M0 emit data via the serial port? Can you not see that data at the end of your transmission chain?