【LPC800 开箱体验】+ 串口打印

Ljmp · 发表于 2016-10-31 16:27:39

板子到手先打印来看看；

贴贴串口代码：

// setup_debug_uart, hard coded to UART0, desired_baudrate/8/N/1
void setup_debug_uart(uint32_t sbond) {
// Select the baud rate
const uint32_t desired_baud = sbond;
// Turn on relevant clocks
LPC_SYSCON->SYSAHBCLKCTRL |= (UART0 | SWM);
// Connect UART0 TXD, RXD signals to port pins
ConfigSWM(U0_TXD, P0_4); // Use with USB-to-RS232 break-out cable
ConfigSWM(U0_RXD, P0_0); // Use with USB-to-RS232 break-out cable
//ConfigSWM(U0_TXD, TARGET_TX); // For MBED serial port (requires board mod.)
//ConfigSWM(U0_RXD, TARGET_RX); // For MBED serial port (requires board mod.)
// UART BRG calculation:
// For asynchronous mode (UART mode) the BRG formula is:
// (BRG + 1) * (1 + (m/256)) * (UARTCLKDIV) * (16 * baudrate Hz.) = MainClock Hz.
// As long as UARTCLKDIV = AHBCLKDIV, and FRG = 1, the System Clock and the UARTn_PCLKs will be the same.
// For this example, we set m = 0 (so FRG = 1), and UARTCLKDIV = AHBCLKDIV.
// Then, we can use the SystemCoreClock variable, as set by the function SystemCoreClockUpdate(),
// in our BRG calculation as follows:
// BRG = (SystemCoreClock Hz. / (16 * desired_baud Hz.)) - 1
// Configure the UARTCLKDIV, default for calculation below is same as AHBCLKDIV
LPC_SYSCON->UARTCLKDIV = LPC_SYSCON->SYSAHBCLKDIV;
// Configure the FRG (default for calculation below is divide-by-1)
LPC_SYSCON->UARTFRGMULT = 0;
LPC_SYSCON->UARTFRGDIV = 255;
// Give USART0 a reset
LPC_SYSCON->PRESETCTRL &= (UART0_RST_N);
LPC_SYSCON->PRESETCTRL |= ~(UART0_RST_N);
// Get the System Clock frequency for the BRG calculation.
SystemCoreClockUpdate();
// Write calculation result to BRG register
LPC_USART0->BRG = (SystemCoreClock / (16 * desired_baud)) - 1;
// Configure the USART0 CFG register:
// 8 data bits, no parity, one stop bit, no flow control, asynchronous mode
LPC_USART0->CFG = DATA_LENG_8|PARITY_NONE|STOP_BIT_1;
// Configure the USART0 CTL register (nothing to be done here)
// No continuous break, no address detect, no Tx disable, no CC, no CLRCC
LPC_USART0->CTL = 0;
// Clear any pending flags (Just to be safe, isn't necessary after the peripheral reset)
LPC_USART0->STAT = 0xFFFF;
// Don't enable the USART0 RX Ready Interrupt, this function assumes a polled use case
//LPC_USART0->INTENSET = RXRDY;
//NVIC_EnableIRQ(UART0_IRQn);
// Enable USART0
LPC_USART0->CFG |= UART_EN;
}
// This is for Keil projects.
uint8_t sendchar (uint8_t ch) {
while (!((LPC_USART0->STAT) & TXRDY)); // Wait for TX Ready
return (LPC_USART0->TXDAT = ch); // Write one character to TX data register
}
void Uprintf(uint8_t *schar)
{
while(*schar !='\0')
{
sendchar(*schar);
schar++;
}
}