题：在工程中添加代码；1.按下“主节点”上的按键"SW1"，控制“从节点”上的D3-D6四个小灯每隔1s流水点亮；（D3-P1.0;D4-P1.1;D5-P1.3;D6-P1.4;SW1-P1.2）
//-------------------------------------------------------------------
// Filename: hal_uart.c
// Description: This file contains the interface to the H/W UART driver.
//-------------------------------------------------------------------
//-------------------------------------------------------------------
// INCLUDES
//-------------------------------------------------------------------
#include "hal_defs.h"
#include "hal_board.h"
#include "hal_uart.h"
//-------------------------------------------------------------------
// MACROS
//-------------------------------------------------------------------
#define HAL_UART_ISR_RX_AVAIL() \
(uartCfg.rxTail >= uartCfg.rxHead) ? \
(uartCfg.rxTail - uartCfg.rxHead) : \
(HAL_UART_ISR_RX_MAX - uartCfg.rxHead + uartCfg.rxTail)
#define HAL_UART_ISR_TX_AVAIL() \
(uartCfg.txHead > uartCfg.txTail) ? \
(uartCfg.txHead - uartCfg.txTail - 1) : \
(HAL_UART_ISR_TX_MAX - uartCfg.txTail + uartCfg.txHead - 1)
//-------------------------------------------------------------------
// TYPEDEFS
//-------------------------------------------------------------------
// U0CSR - USART Control and Status Register.
#define CSR_MODE 0x80
#define CSR_RE 0x40
#define CSR_SLAVE 0x20
#define CSR_FE 0x10
#define CSR_ERR 0x08
#define CSR_RX_BYTE 0x04
#define CSR_TX_BYTE 0x02
#define CSR_ACTIVE 0x01
// U0UCR - USART UART Control Register.
#define UCR_FLUSH 0x80
#define UCR_FLOW 0x40
#define UCR_D9 0x20
#define UCR_BIT9 0x10
#define UCR_PARITY 0x08
#define UCR_SPB 0x04
#define UCR_STOP 0x02
#define UCR_START 0x01
#define UTX0IE 0x04
#define U0RX_TX 0x0C
#define HAL_UART_PERCFG_BIT 0x01
#define HAL_UART_ISR_RX_MAX 128
#define HAL_UART_ISR_TX_MAX HAL_UART_ISR_RX_MAX
typedef struct
{
uint8 rxBuf[HAL_UART_ISR_RX_MAX];
uint8 rxHead;
volatile uint8 rxTail;
uint8 rxShdw;
uint8 txBuf[HAL_UART_ISR_TX_MAX];
volatile uint8 txHead;
uint8 txTail;
uint8 txMT;
} uartCfg_t;
//-------------------------------------------------------------------
// LOCAL VARIABLES
//-------------------------------------------------------------------
uartCfg_t uartCfg;
//-------------------------------------------------------------------
// @fn halUartInit
// @brief Initialize the UART
// @param none
// @return none
//-------------------------------------------------------------------
void halUartInit(uint32 baud)
{
// UART Configuration
PERCFG &= ~HAL_UART_PERCFG_BIT; // Set UART0 I/O location to P0.
P0SEL |= U0RX_TX; // Enable Tx and Rx peripheral functions on pins.
ADCCFG &= ~U0RX_TX; // Make sure ADC doesnt use this.
U0CSR = CSR_MODE; // Mode is UART Mode.
U0UCR = UCR_FLUSH; // Flush it.
// Only supporting subset of baudrate for code size - other is possible.
// 38400
//U0BAUD = 59;
//U0GCR = 10;
// 9600
//U0BAUD = 59;
//U0GCR = 8;
//U0BAUD = value_u0baud;
//U0GCR = value_u0gcr;
switch(baud)
{
case 1200 :
U0BAUD = 59; U0GCR = 5; break;
case 2400 :
U0BAUD = 59; U0GCR = 6; break;
case 4800 :
U0BAUD = 59; U0GCR = 7; break;
case 9600 :
U0BAUD = 59; U0GCR = 8; break;
case 14400 :
U0BAUD = 216; U0GCR = 8; break;
case 19200 :
U0BAUD = 59; U0GCR = 9; break;
case 28800 :
U0BAUD = 216; U0GCR = 9; break;
case 38400 :
U0BAUD = 59; U0GCR = 10; break;
case 57600 :
U0BAUD = 216; U0GCR = 10; break;
case 76800 :
U0BAUD = 59; U0GCR = 11; break;
case 115200 :
U0BAUD = 216; U0GCR = 11; break;
case 230400 :
U0BAUD = 216; U0GCR = 12; break;
default :
U0BAUD = 59; U0GCR = 10; break;
}
// 8 bits/char; no parity; 1 stop bit; stop bit hi.
U0UCR = UCR_STOP;
U0CSR |= CSR_RE;
URX0IE = 1;
U0DBUF = 0; // Prime the ISR pump.
uartCfg.rxHead = 0;
uartCfg.rxTail = 0;
uartCfg.txHead = 0;
uartCfg.txTail = 0;
uartCfg.rxShdw = 0;
uartCfg.txMT = 0;
}
//-------------------------------------------------------------------
// @fn halUartRead
// @brief Read a buffer from the UART
// @param buf - valid data buffer at least 'len' bytes in size
// len - max length number of bytes to copy to 'buf'
// @return length of buffer that was read
//-------------------------------------------------------------------
uint16 halUartRead(uint8 *buf, uint16 len)
{
uint16 cnt = 0;
while ((uartCfg.rxHead != uartCfg.rxTail) && (cnt < len))
{
*buf++ = uartCfg.rxBuf[uartCfg.rxHead++];
if (uartCfg.rxHead >= HAL_UART_ISR_RX_MAX)
{
uartCfg.rxHead = 0;
}
cnt++;
}
return cnt;
}
//-------------------------------------------------------------------
// @fn halUartWrite
// @brief Write a buffer to the UART.
// @param buf - pointer to the buffer that will be written, not freed
// len - length of
// @return length of the buffer that was sent
//-------------------------------------------------------------------
uint16 halUartWrite(uint8 *buf, uint16 len)
{
uint16 cnt;
// Accept "all-or-none" on write request.
if (HAL_UART_ISR_TX_AVAIL() < len)
{
return 0;
}
for (cnt = 0; cnt < len; cnt++)
{
uartCfg.txBuf[uartCfg.txTail] = *buf++;
uartCfg.txMT = 0;
if (uartCfg.txTail >= HAL_UART_ISR_TX_MAX - 1)
{
uartCfg.txTail = 0;
}
else
{
uartCfg.txTail++;
}
// Keep re-enabling ISR as it might be keeping up with this loop due to other ints.
IEN2 |= UTX0IE;
}
return cnt;
}
//-------------------------------------------------------------------
// @fn halUartRxLen()
// @brief Calculate Rx Buffer length - the number of bytes in the buffer.
// @param none
// @return length of current Rx Buffer
//-------------------------------------------------------------------
uint16 halUartRxLen(void)
{
return HAL_UART_ISR_RX_AVAIL();
}
//-------------------------------------------------------------------
// @fn halUartSuspend
// @brief Suspend UART hardware before entering PM mode 1, 2 or 3.
// @param None
// @return None
//-------------------------------------------------------------------
void halUartSuspend(void)
{
U0CSR &= ~CSR_RE;
}
//-------------------------------------------------------------------
// @fn halUartResume
// @brief Resume UART hardware after exiting PM mode 1, 2 or 3.
// @param None
// @return None
//-------------------------------------------------------------------
void halUartResume(void)
{
U0UCR |= UCR_FLUSH;
U0CSR |= CSR_RE;
}
//-------------------------------------------------------------------
// @fn halUartRxIsr
// @brief UART Receive Interrupt
// @param None
// @return None
//-------------------------------------------------------------------
HAL_ISR_FUNCTION(halUart0RxIsr, URX0_VECTOR)
{
uint8 tmp = U0DBUF;
uartCfg.rxBuf[uartCfg.rxTail] = tmp;
// Re-sync the shadow on any 1st byte received.
if (uartCfg.rxHead == uartCfg.rxTail)
{
uartCfg.rxShdw = ST0;
}
if (++uartCfg.rxTail >= HAL_UART_ISR_RX_MAX)
{
uartCfg.rxTail = 0;
}
}
//-------------------------------------------------------------------
// @fn halUartTxIsr
// @brief UART Transmit Interrupt
// @param None
// @return None
//-------------------------------------------------------------------
HAL_ISR_FUNCTION(halUart0TxIsr, UTX0_VECTOR)
{
if (uartCfg.txHead == uartCfg.txTail)
{
IEN2 &= ~UTX0IE;
uartCfg.txMT = 1;
}
else
{
UTX0IF = 0;
U0DBUF = uartCfg.txBuf[uartCfg.txHead++];
if (uartCfg.txHead >= HAL_UART_ISR_TX_MAX)
{
uartCfg.txHead = 0;
}
}
}
求大神解答！！