I'm working on a project in which the MCU LPC1768 will be connected to a host.
The host will send command message to UART1 of MCU LPC1768 and the MCU will reply with a predefined message. There are a series of command messages from the host. The sequences are: 1) From Host to MCU: "UART_On" From MCU to Host: "UART_On_Done"
2) From Host to MCU: "UART_Off" From MCU to Host: "UART_Off_Done" and etc...
What happens is that I send "UART_On" to the MCU and it replies with "UART_On_Done". Then, I send "UART_Off". The MCU will reply with "UART_On_Done" or "UART_On_DoneUART_On_Done". What I want is like what I wrote above.
I wrote the code based on UART example of mcb1700.code.bundle.lpc17xx.keil.
My main codes are as below. I also attach my source code. Please kindly help to see what's wrong and give me any suggestions. Thank you soooo much!
uarttest.c
... int main (void) { SystemClockUpdate(); UARTInit(1, 115200); /* baud rate setting */ while (1) { /* Loop forever */ if ( UART1Count != 0 ) { LPC_UART1->IER = IER_THRE | IER_RLS; /* Disable RBR */ if (strstr((const char *)UART1Buffer, "UART_On")) { UARTSend( 1, "UART_On_Done", 12); UART1Count = 0; } if (strstr((const char *)UART1Buffer, "UART_Off")) { UARTSend( 1, "UART_Off_Done", 13); UART1Count = 0; } LPC_UART1->IER = IER_THRE | IER_RLS | IER_RBR; /* Re-enable RBR */ } } }
uart.c
... void UART1_IRQHandler (void) { uint8_t IIRValue, LSRValue; uint8_t Dummy = Dummy; IIRValue = LPC_UART1->IIR; IIRValue >>= 1; /* skip pending bit in IIR */ IIRValue &= 0x07; /* check bit 1~3, interrupt identification */ if ( IIRValue == IIR_RLS ) /* Receive Line Status */ { LSRValue = LPC_UART1->LSR; /* Receive Line Status */ if ( LSRValue & (LSR_OE|LSR_PE|LSR_FE|LSR_RXFE|LSR_BI) ) { /* There are errors or break interrupt */ /* Read LSR will clear the interrupt */ UART1Status = LSRValue; Dummy = LPC_UART1->RBR; /* Dummy read on RX to clear interrupt, then bail out */ return; } if ( LSRValue & LSR_RDR ) /* Receive Data Ready */ { /* If no error on RLS, normal ready, save into the data buffer. */ /* Note: read RBR will clear the interrupt */ UART1Buffer[UART1Count] = LPC_UART1->RBR; UART1Count++; if ( UART1Count == BUFSIZE ) { UART1Count = 0; /* buffer overflow */ } } } else if ( IIRValue == IIR_RDA ) /* Receive Data Available */ { /* Receive Data Available */ UART1Buffer[UART1Count] = LPC_UART1->RBR; UART1Count++; if ( UART1Count == BUFSIZE ) { UART1Count = 0; /* buffer overflow */ } } else if ( IIRValue == IIR_CTI ) /* Character timeout indicator */ { /* Character Time-out indicator */ UART1Status |= 0x100; /* Bit 9 as the CTI error */ } else if ( IIRValue == IIR_THRE ) /* THRE, transmit holding register empty */ { /* THRE interrupt */ LSRValue = LPC_UART1->LSR; /* Check status in the LSR to see if valid data in U0THR or not */ if ( LSRValue & LSR_THRE ) { UART1TxEmpty = 1; } else { UART1TxEmpty = 0; } } } uint32_t UARTInit( uint32_t PortNum, uint32_t baudrate ) { uint32_t Fdiv; uint32_t pclkdiv, pclk; if ( PortNum == 0 ) { LPC_PINCON->PINSEL0 &= ~0x000000F0; LPC_PINCON->PINSEL0 |= 0x00000050; /* RxD0 is P0.3 and TxD0 is P0.2 */ /* By default, the PCLKSELx value is zero, thus, the PCLK for all the peripherals is 1/4 of the SystemFrequency. */ /* Bit 6~7 is for UART0 */ pclkdiv = (LPC_SC->PCLKSEL0 >> 6) & 0x03; switch ( pclkdiv ) { case 0x00: default: pclk = SystemFrequency/4; break; case 0x01: pclk = SystemFrequency; break; case 0x02: pclk = SystemFrequency/2; break; case 0x03: pclk = SystemFrequency/8; break; } LPC_UART0->LCR = 0x83; /* 8 bits, no Parity, 1 Stop bit */ Fdiv = ( pclk / 16 ) / baudrate ; /*baud rate */ LPC_UART0->DLM = Fdiv / 256; LPC_UART0->DLL = Fdiv % 256; LPC_UART0->LCR = 0x03; /* DLAB = 0 */ LPC_UART0->FCR = 0x07; /* Enable and reset TX and RX FIFO. */ NVIC_EnableIRQ(UART0_IRQn); LPC_UART0->IER = IER_RBR | IER_THRE | IER_RLS; /* Enable UART0 interrupt */ return (TRUE); } else if ( PortNum == 1 ) { LPC_PINCON->PINSEL4 &= ~0x0000000F; LPC_PINCON->PINSEL4 |= 0x0000000A; /* Enable RxD1 P2.1, TxD1 P2.0 */ /* By default, the PCLKSELx value is zero, thus, the PCLK for all the peripherals is 1/4 of the SystemFrequency. */ /* Bit 8,9 are for UART1 */ pclkdiv = (LPC_SC->PCLKSEL0 >> 8) & 0x03; switch ( pclkdiv ) { case 0x00: default: pclk = SystemFrequency/4; break; case 0x01: pclk = SystemFrequency; break; case 0x02: pclk = SystemFrequency/2; break; case 0x03: pclk = SystemFrequency/8; break; } LPC_UART1->LCR = 0x83; /* 8 bits, no Parity, 1 Stop bit */ Fdiv = ( pclk / 16 ) / baudrate ; /*baud rate */ LPC_UART1->DLM = Fdiv / 256; LPC_UART1->DLL = Fdiv % 256; LPC_UART1->LCR = 0x03; /* DLAB = 0 */ LPC_UART1->FCR = 0x07; /* Enable and reset TX and RX FIFO. */ NVIC_EnableIRQ(UART1_IRQn); LPC_UART1->IER = IER_RBR | IER_THRE | IER_RLS; /* Enable UART1 interrupt */ return (TRUE); } return( FALSE ); } void UARTSend( uint32_t portNum, uint8_t *BufferPtr, uint32_t Length ) { if ( portNum == 0 ) { while ( Length != 0 ) { /* THRE status, contain valid data */ while ( !(UART0TxEmpty & 0x01) ); LPC_UART0->THR = *BufferPtr; UART0TxEmpty = 0; /* not empty in the THR until it shifts out */ BufferPtr++; Length--; } } else { while ( Length != 0 ) { /* THRE status, contain valid data */ while ( !(UART1TxEmpty & 0x01) ); LPC_UART1->THR = *BufferPtr; UART1TxEmpty = 0; /* not empty in the THR until it shifts out */ BufferPtr++; Length--; } } return; }
Have you stepped through it in the Debugger to see where it's going wrong?