TI中文支持网程序如下所示，请问这个程序是什么时候产生中断的，怎么从main的空循环里跳出到中断服务子程序的，谢谢？
//###########################################################################
//
//! \addtogroup f2803x_example_list
//! <h1>SPI Digital Loop Back with Interrupts(spi_loopback_interrupts)</h1>
//!
//! This program uses the internal loop back test mode of the peripheral.
//! Other then boot mode pin configuration, no other hardware configuration
//! is required. Both interrupts and the SPI FIFOs are used.
//!
//! A stream of data is sent and then compared to the received stream.
//! The sent data looks like this: \n
//! 0000 0001 \n
//! 0001 0002 \n
//! 0002 0003 \n
//! .... \n
//! FFFE FFFF \n
//! FFFF 0000 \n
//! etc.. \n
//! This pattern is repeated forever.
//!
//! \b Watch \b Variables \n
//! - \b sdata , Data to send
//! - \b rdata , Received data
//! - \b rdata_point , Used to keep track of the last position in
//!the receive stream for error checking
//
//###########################################################################
// $TI Release: F2803x C/C++ Header Files and Peripheral Examples V127 $
// $Release Date: March 30, 2013 $
//###########################################################################
#include "DSP28x_Project.h"// Device Headerfile and Examples Include File
// Prototype statements for functions found within this file.
// interrupt void ISRTimer2(void);
__interrupt void spiTxFifoIsr(void);
__interrupt void spiRxFifoIsr(void);
void delay_loop(void);
void spi_fifo_init(void);
void error();
Uint16 sdata[2];// Send data buffer
Uint16 rdata[2];// Receive data buffer
Uint16 rdata_point; // Keep track of where we are// in the data stream to check received data
void main(void)
{Uint16 i;
// Step 1. Initialize System Control:
// PLL, WatchDog, enable Peripheral Clocks
// This example function is found in the DSP2803x_SysCtrl.c file.InitSysCtrl();
// Step 2. Initalize GPIO:
// This example function is found in the DSP2803x_Gpio.c file and
// illustrates how to set the GPIO to it's default state.
// InitGpio(); // Skipped for this example
// Setup only the GP I/O only for SPI-A functionalityInitSpiaGpio();
// Step 3. Initialize PIE vector table:
// Disable and clear all CPU interruptsDINT;IER = 0x0000;IFR = 0x0000;
// Initialize PIE control registers to their default state:
// This function is found in the DSP2803x_PieCtrl.c file.InitPieCtrl();
// Initialize the PIE vector table with pointers to the shell Interrupt
// Service Routines (ISR).
// This will populate the entire table, even if the interrupt
// is not used in this example. This is useful for debug purposes.
// The shell ISR routines are found in DSP2803x_DefaultIsr.c.
// This function is found in DSP2803x_PieVect.c.InitPieVectTable();
// Interrupts that are used in this example are re-mapped to
// ISR functions found within this file.EALLOW; // This is needed to write to EALLOW protected registersPieVectTable.SPIRXINTA = &spiRxFifoIsr;PieVectTable.SPITXINTA = &spiTxFifoIsr;EDIS;// This is needed to disable write to EALLOW protected registers
// Step 4. Initialize all the Device Peripherals:
// This function is found in DSP2803x_InitPeripherals.c
// InitPeripherals(); // Not required for this examplespi_fifo_init();// Initialize the SPI only
// Step 5. User specific code, enable interrupts:
// Initalize the send data bufferfor(i=0; i<2; i++){sdata[i] = i;}rdata_point = 0;
// Enable interrupts required for this examplePieCtrlRegs.PIECTRL.bit.ENPIE = 1;// Enable the PIE blockPieCtrlRegs.PIEIER6.bit.INTx1=1;// Enable PIE Group 6, INT 1PieCtrlRegs.PIEIER6.bit.INTx2=1;// Enable PIE Group 6, INT 2IER=0x20;// Enable CPU INT6EINT;// Enable Global Interrupts
// Step 6. IDLE loop. Just sit and loop forever (optional):for(;;);
}
// Some Useful local functions
void delay_loop()
{longi;for (i = 0; i < 1000000; i++) {}
}
void error(void)
{__asm("ESTOP0"); //Test failed!! Stop!for (;;);
}
void spi_fifo_init()
{
// Initialize SPI FIFO registersSpiaRegs.SPICCR.bit.SPISWRESET=0; // Reset SPISpiaRegs.SPICCR.all=0x001F;//16-bit character, Loopback modeSpiaRegs.SPICTL.all=0x0017;//Interrupt enabled, Master/Slave XMIT enabledSpiaRegs.SPISTS.all=0x0000;SpiaRegs.SPIBRR=0x0063;// Baud rateSpiaRegs.SPIFFTX.all=0xC022;// Enable FIFO's, set TX FIFO level to 2 1100 0000 0010 0010SpiaRegs.SPIFFRX.all=0x0022;// Set RX FIFO level to 2SpiaRegs.SPIFFCT.all=0x00;SpiaRegs.SPIPRI.all=0x0010;SpiaRegs.SPICCR.bit.SPISWRESET=1; // Enable SPISpiaRegs.SPIFFTX.bit.TXFIFO=1;SpiaRegs.SPIFFRX.bit.RXFIFORESET=1;
}
__interrupt void spiTxFifoIsr(void)
{Uint16 i;for(i=0;i<2;i++){SpiaRegs.SPITXBUF=sdata[i];// Send data}
//
// Increment data buffer contents by 1 for
// the next transmit cycle
//for(i=0;i<2;i++){sdata[i] = sdata[i] + 1;}SpiaRegs.SPIFFTX.bit.TXFFINTCLR=1; // Clear Interrupt flagPieCtrlRegs.PIEACK.all|=0x20;// Issue PIE ACK
}
__interrupt void spiRxFifoIsr(void)
{Uint16 i;for(i=0;i<2;i++){rdata[i]=SpiaRegs.SPIRXBUF;// Read data}for(i=0;i<2;i++)// Check received data{if(rdata[i] != rdata_point+i) error();}rdata_point++;SpiaRegs.SPIFFRX.bit.RXFFOVFCLR=1; // Clear Overflow flagSpiaRegs.SPIFFRX.bit.RXFFINTCLR=1; // Clear Interrupt flagPieCtrlRegs.PIEACK.all|=0x20;// Issue PIE ack
}
//===========================================================================
// No more.
//===========================================================================
Joey Mao：
你好，
你要明白中断的原理，中断被使能后和初始化后，根据设定的定时周期进行周期性循环，而主循环是在程序运行起来后就无限循环的。
它们在一定程度上是相互独立的。当中断周期数达到，开始执行中断程序，主循环被挂起；而中断程序执行完后主循环程序继续执行。
程序如下所示，请问这个程序是什么时候产生中断的，怎么从main的空循环里跳出到中断服务子程序的，谢谢？
//###########################################################################
//
//! \addtogroup f2803x_example_list
//! <h1>SPI Digital Loop Back with Interrupts(spi_loopback_interrupts)</h1>
//!
//! This program uses the internal loop back test mode of the peripheral.
//! Other then boot mode pin configuration, no other hardware configuration
//! is required. Both interrupts and the SPI FIFOs are used.
//!
//! A stream of data is sent and then compared to the received stream.
//! The sent data looks like this: \n
//! 0000 0001 \n
//! 0001 0002 \n
//! 0002 0003 \n
//! .... \n
//! FFFE FFFF \n
//! FFFF 0000 \n
//! etc.. \n
//! This pattern is repeated forever.
//!
//! \b Watch \b Variables \n
//! - \b sdata , Data to send
//! - \b rdata , Received data
//! - \b rdata_point , Used to keep track of the last position in
//!the receive stream for error checking
//
//###########################################################################
// $TI Release: F2803x C/C++ Header Files and Peripheral Examples V127 $
// $Release Date: March 30, 2013 $
//###########################################################################
#include "DSP28x_Project.h"// Device Headerfile and Examples Include File
// Prototype statements for functions found within this file.
// interrupt void ISRTimer2(void);
__interrupt void spiTxFifoIsr(void);
__interrupt void spiRxFifoIsr(void);
void delay_loop(void);
void spi_fifo_init(void);
void error();
Uint16 sdata[2];// Send data buffer
Uint16 rdata[2];// Receive data buffer
Uint16 rdata_point; // Keep track of where we are// in the data stream to check received data
void main(void)
{Uint16 i;
// Step 1. Initialize System Control:
// PLL, WatchDog, enable Peripheral Clocks
// This example function is found in the DSP2803x_SysCtrl.c file.InitSysCtrl();
// Step 2. Initalize GPIO:
// This example function is found in the DSP2803x_Gpio.c file and
// illustrates how to set the GPIO to it's default state.
// InitGpio(); // Skipped for this example
// Setup only the GP I/O only for SPI-A functionalityInitSpiaGpio();
// Step 3. Initialize PIE vector table:
// Disable and clear all CPU interruptsDINT;IER = 0x0000;IFR = 0x0000;
// Initialize PIE control registers to their default state:
// This function is found in the DSP2803x_PieCtrl.c file.InitPieCtrl();
// Initialize the PIE vector table with pointers to the shell Interrupt
// Service Routines (ISR).
// This will populate the entire table, even if the interrupt
// is not used in this example. This is useful for debug purposes.
// The shell ISR routines are found in DSP2803x_DefaultIsr.c.
// This function is found in DSP2803x_PieVect.c.InitPieVectTable();
// Interrupts that are used in this example are re-mapped to
// ISR functions found within this file.EALLOW; // This is needed to write to EALLOW protected registersPieVectTable.SPIRXINTA = &spiRxFifoIsr;PieVectTable.SPITXINTA = &spiTxFifoIsr;EDIS;// This is needed to disable write to EALLOW protected registers
// Step 4. Initialize all the Device Peripherals:
// This function is found in DSP2803x_InitPeripherals.c
// InitPeripherals(); // Not required for this examplespi_fifo_init();// Initialize the SPI only
// Step 5. User specific code, enable interrupts:
// Initalize the send data bufferfor(i=0; i<2; i++){sdata[i] = i;}rdata_point = 0;
// Enable interrupts required for this examplePieCtrlRegs.PIECTRL.bit.ENPIE = 1;// Enable the PIE blockPieCtrlRegs.PIEIER6.bit.INTx1=1;// Enable PIE Group 6, INT 1PieCtrlRegs.PIEIER6.bit.INTx2=1;// Enable PIE Group 6, INT 2IER=0x20;// Enable CPU INT6EINT;// Enable Global Interrupts
// Step 6. IDLE loop. Just sit and loop forever (optional):for(;;);
}
// Some Useful local functions
void delay_loop()
{longi;for (i = 0; i < 1000000; i++) {}
}
void error(void)
{__asm("ESTOP0"); //Test failed!! Stop!for (;;);
}
void spi_fifo_init()
{
// Initialize SPI FIFO registersSpiaRegs.SPICCR.bit.SPISWRESET=0; // Reset SPISpiaRegs.SPICCR.all=0x001F;//16-bit character, Loopback modeSpiaRegs.SPICTL.all=0x0017;//Interrupt enabled, Master/Slave XMIT enabledSpiaRegs.SPISTS.all=0x0000;SpiaRegs.SPIBRR=0x0063;// Baud rateSpiaRegs.SPIFFTX.all=0xC022;// Enable FIFO's, set TX FIFO level to 2 1100 0000 0010 0010SpiaRegs.SPIFFRX.all=0x0022;// Set RX FIFO level to 2SpiaRegs.SPIFFCT.all=0x00;SpiaRegs.SPIPRI.all=0x0010;SpiaRegs.SPICCR.bit.SPISWRESET=1; // Enable SPISpiaRegs.SPIFFTX.bit.TXFIFO=1;SpiaRegs.SPIFFRX.bit.RXFIFORESET=1;
}
__interrupt void spiTxFifoIsr(void)
{Uint16 i;for(i=0;i<2;i++){SpiaRegs.SPITXBUF=sdata[i];// Send data}
//
// Increment data buffer contents by 1 for
// the next transmit cycle
//for(i=0;i<2;i++){sdata[i] = sdata[i] + 1;}SpiaRegs.SPIFFTX.bit.TXFFINTCLR=1; // Clear Interrupt flagPieCtrlRegs.PIEACK.all|=0x20;// Issue PIE ACK
}
__interrupt void spiRxFifoIsr(void)
{Uint16 i;for(i=0;i<2;i++){rdata[i]=SpiaRegs.SPIRXBUF;// Read data}for(i=0;i<2;i++)// Check received data{if(rdata[i] != rdata_point+i) error();}rdata_point++;SpiaRegs.SPIFFRX.bit.RXFFOVFCLR=1; // Clear Overflow flagSpiaRegs.SPIFFRX.bit.RXFFINTCLR=1; // Clear Interrupt flagPieCtrlRegs.PIEACK.all|=0x20;// Issue PIE ack
}
//===========================================================================
// No more.
//===========================================================================
yuan michael：
回复 Joey Mao:
Joey Mao，
你好，谢谢你的回答。
中断不应该是由某一事件触发的吗？
程序如下所示，请问这个程序是什么时候产生中断的，怎么从main的空循环里跳出到中断服务子程序的，谢谢？
//###########################################################################
//
//! \addtogroup f2803x_example_list
//! <h1>SPI Digital Loop Back with Interrupts(spi_loopback_interrupts)</h1>
//!
//! This program uses the internal loop back test mode of the peripheral.
//! Other then boot mode pin configuration, no other hardware configuration
//! is required. Both interrupts and the SPI FIFOs are used.
//!
//! A stream of data is sent and then compared to the received stream.
//! The sent data looks like this: \n
//! 0000 0001 \n
//! 0001 0002 \n
//! 0002 0003 \n
//! .... \n
//! FFFE FFFF \n
//! FFFF 0000 \n
//! etc.. \n
//! This pattern is repeated forever.
//!
//! \b Watch \b Variables \n
//! - \b sdata , Data to send
//! - \b rdata , Received data
//! - \b rdata_point , Used to keep track of the last position in
//!the receive stream for error checking
//
//###########################################################################
// $TI Release: F2803x C/C++ Header Files and Peripheral Examples V127 $
// $Release Date: March 30, 2013 $
//###########################################################################
#include "DSP28x_Project.h"// Device Headerfile and Examples Include File
// Prototype statements for functions found within this file.
// interrupt void ISRTimer2(void);
__interrupt void spiTxFifoIsr(void);
__interrupt void spiRxFifoIsr(void);
void delay_loop(void);
void spi_fifo_init(void);
void error();
Uint16 sdata[2];// Send data buffer
Uint16 rdata[2];// Receive data buffer
Uint16 rdata_point; // Keep track of where we are// in the data stream to check received data
void main(void)
{Uint16 i;
// Step 1. Initialize System Control:
// PLL, WatchDog, enable Peripheral Clocks
// This example function is found in the DSP2803x_SysCtrl.c file.InitSysCtrl();
// Step 2. Initalize GPIO:
// This example function is found in the DSP2803x_Gpio.c file and
// illustrates how to set the GPIO to it's default state.
// InitGpio(); // Skipped for this example
// Setup only the GP I/O only for SPI-A functionalityInitSpiaGpio();
// Step 3. Initialize PIE vector table:
// Disable and clear all CPU interruptsDINT;IER = 0x0000;IFR = 0x0000;
// Initialize PIE control registers to their default state:
// This function is found in the DSP2803x_PieCtrl.c file.InitPieCtrl();
// Initialize the PIE vector table with pointers to the shell Interrupt
// Service Routines (ISR).
// This will populate the entire table, even if the interrupt
// is not used in this example. This is useful for debug purposes.
// The shell ISR routines are found in DSP2803x_DefaultIsr.c.
// This function is found in DSP2803x_PieVect.c.InitPieVectTable();
// Interrupts that are used in this example are re-mapped to
// ISR functions found within this file.EALLOW; // This is needed to write to EALLOW protected registersPieVectTable.SPIRXINTA = &spiRxFifoIsr;PieVectTable.SPITXINTA = &spiTxFifoIsr;EDIS;// This is needed to disable write to EALLOW protected registers
// Step 4. Initialize all the Device Peripherals:
// This function is found in DSP2803x_InitPeripherals.c
// InitPeripherals(); // Not required for this examplespi_fifo_init();// Initialize the SPI only
// Step 5. User specific code, enable interrupts:
// Initalize the send data bufferfor(i=0; i<2; i++){sdata[i] = i;}rdata_point = 0;
// Enable interrupts required for this examplePieCtrlRegs.PIECTRL.bit.ENPIE = 1;// Enable the PIE blockPieCtrlRegs.PIEIER6.bit.INTx1=1;// Enable PIE Group 6, INT 1PieCtrlRegs.PIEIER6.bit.INTx2=1;// Enable PIE Group 6, INT 2IER=0x20;// Enable CPU INT6EINT;// Enable Global Interrupts
// Step 6. IDLE loop. Just sit and loop forever (optional):for(;;);
}
// Some Useful local functions
void delay_loop()
{longi;for (i = 0; i < 1000000; i++) {}
}
void error(void)
{__asm("ESTOP0"); //Test failed!! Stop!for (;;);
}
void spi_fifo_init()
{
// Initialize SPI FIFO registersSpiaRegs.SPICCR.bit.SPISWRESET=0; // Reset SPISpiaRegs.SPICCR.all=0x001F;//16-bit character, Loopback modeSpiaRegs.SPICTL.all=0x0017;//Interrupt enabled, Master/Slave XMIT enabledSpiaRegs.SPISTS.all=0x0000;SpiaRegs.SPIBRR=0x0063;// Baud rateSpiaRegs.SPIFFTX.all=0xC022;// Enable FIFO's, set TX FIFO level to 2 1100 0000 0010 0010SpiaRegs.SPIFFRX.all=0x0022;// Set RX FIFO level to 2SpiaRegs.SPIFFCT.all=0x00;SpiaRegs.SPIPRI.all=0x0010;SpiaRegs.SPICCR.bit.SPISWRESET=1; // Enable SPISpiaRegs.SPIFFTX.bit.TXFIFO=1;SpiaRegs.SPIFFRX.bit.RXFIFORESET=1;
}
__interrupt void spiTxFifoIsr(void)
{Uint16 i;for(i=0;i<2;i++){SpiaRegs.SPITXBUF=sdata[i];// Send data}
//
// Increment data buffer contents by 1 for
// the next transmit cycle
//for(i=0;i<2;i++){sdata[i] = sdata[i] + 1;}SpiaRegs.SPIFFTX.bit.TXFFINTCLR=1; // Clear Interrupt flagPieCtrlRegs.PIEACK.all|=0x20;// Issue PIE ACK
}
__interrupt void spiRxFifoIsr(void)
{Uint16 i;for(i=0;i<2;i++){rdata[i]=SpiaRegs.SPIRXBUF;// Read data}for(i=0;i<2;i++)// Check received data{if(rdata[i] != rdata_point+i) error();}rdata_point++;SpiaRegs.SPIFFRX.bit.RXFFOVFCLR=1; // Clear Overflow flagSpiaRegs.SPIFFRX.bit.RXFFINTCLR=1; // Clear Interrupt flagPieCtrlRegs.PIEACK.all|=0x20;// Issue PIE ack
}
//===========================================================================
// No more.
//===========================================================================
yaogang Ye：
回复 Joey Mao:
你好Joey Mao，
我其实也是对这个问题困惑很久，SPI的通讯中断时怎么通过周期性时间触发的？就拿这个例子来说，在主程序里也没有涉及到设置定时器或者故障中断啊。
程序如下所示，请问这个程序是什么时候产生中断的，怎么从main的空循环里跳出到中断服务子程序的，谢谢？
//###########################################################################
//
//! \addtogroup f2803x_example_list
//! <h1>SPI Digital Loop Back with Interrupts(spi_loopback_interrupts)</h1>
//!
//! This program uses the internal loop back test mode of the peripheral.
//! Other then boot mode pin configuration, no other hardware configuration
//! is required. Both interrupts and the SPI FIFOs are used.
//!
//! A stream of data is sent and then compared to the received stream.
//! The sent data looks like this: \n
//! 0000 0001 \n
//! 0001 0002 \n
//! 0002 0003 \n
//! .... \n
//! FFFE FFFF \n
//! FFFF 0000 \n
//! etc.. \n
//! This pattern is repeated forever.
//!
//! \b Watch \b Variables \n
//! - \b sdata , Data to send
//! - \b rdata , Received data
//! - \b rdata_point , Used to keep track of the last position in
//!the receive stream for error checking
//
//###########################################################################
// $TI Release: F2803x C/C++ Header Files and Peripheral Examples V127 $
// $Release Date: March 30, 2013 $
//###########################################################################
#include "DSP28x_Project.h"// Device Headerfile and Examples Include File
// Prototype statements for functions found within this file.
// interrupt void ISRTimer2(void);
__interrupt void spiTxFifoIsr(void);
__interrupt void spiRxFifoIsr(void);
void delay_loop(void);
void spi_fifo_init(void);
void error();
Uint16 sdata[2];// Send data buffer
Uint16 rdata[2];// Receive data buffer
Uint16 rdata_point; // Keep track of where we are// in the data stream to check received data
void main(void)
{Uint16 i;
// Step 1. Initialize System Control:
// PLL, WatchDog, enable Peripheral Clocks
// This example function is found in the DSP2803x_SysCtrl.c file.InitSysCtrl();
// Step 2. Initalize GPIO:
// This example function is found in the DSP2803x_Gpio.c file and
// illustrates how to set the GPIO to it's default state.
// InitGpio(); // Skipped for this example
// Setup only the GP I/O only for SPI-A functionalityInitSpiaGpio();
// Step 3. Initialize PIE vector table:
// Disable and clear all CPU interruptsDINT;IER = 0x0000;IFR = 0x0000;
// Initialize PIE control registers to their default state:
// This function is found in the DSP2803x_PieCtrl.c file.InitPieCtrl();
// Initialize the PIE vector table with pointers to the shell Interrupt
// Service Routines (ISR).
// This will populate the entire table, even if the interrupt
// is not used in this example. This is useful for debug purposes.
// The shell ISR routines are found in DSP2803x_DefaultIsr.c.
// This function is found in DSP2803x_PieVect.c.InitPieVectTable();
// Interrupts that are used in this example are re-mapped to
// ISR functions found within this file.EALLOW; // This is needed to write to EALLOW protected registersPieVectTable.SPIRXINTA = &spiRxFifoIsr;PieVectTable.SPITXINTA = &spiTxFifoIsr;EDIS;// This is needed to disable write to EALLOW protected registers
// Step 4. Initialize all the Device Peripherals:
// This function is found in DSP2803x_InitPeripherals.c
// InitPeripherals(); // Not required for this examplespi_fifo_init();// Initialize the SPI only
// Step 5. User specific code, enable interrupts:
// Initalize the send data bufferfor(i=0; i<2; i++){sdata[i] = i;}rdata_point = 0;
// Enable interrupts required for this examplePieCtrlRegs.PIECTRL.bit.ENPIE = 1;// Enable the PIE blockPieCtrlRegs.PIEIER6.bit.INTx1=1;// Enable PIE Group 6, INT 1PieCtrlRegs.PIEIER6.bit.INTx2=1;// Enable PIE Group 6, INT 2IER=0x20;// Enable CPU INT6EINT;// Enable Global Interrupts
// Step 6. IDLE loop. Just sit and loop forever (optional):for(;;);
}
// Some Useful local functions
void delay_loop()
{longi;for (i = 0; i < 1000000; i++) {}
}
void error(void)
{__asm("ESTOP0"); //Test failed!! Stop!for (;;);
}
void spi_fifo_init()
{
// Initialize SPI FIFO registersSpiaRegs.SPICCR.bit.SPISWRESET=0; // Reset SPISpiaRegs.SPICCR.all=0x001F;//16-bit character, Loopback modeSpiaRegs.SPICTL.all=0x0017;//Interrupt enabled, Master/Slave XMIT enabledSpiaRegs.SPISTS.all=0x0000;SpiaRegs.SPIBRR=0x0063;// Baud rateSpiaRegs.SPIFFTX.all=0xC022;// Enable FIFO's, set TX FIFO level to 2 1100 0000 0010 0010SpiaRegs.SPIFFRX.all=0x0022;// Set RX FIFO level to 2SpiaRegs.SPIFFCT.all=0x00;SpiaRegs.SPIPRI.all=0x0010;SpiaRegs.SPICCR.bit.SPISWRESET=1; // Enable SPISpiaRegs.SPIFFTX.bit.TXFIFO=1;SpiaRegs.SPIFFRX.bit.RXFIFORESET=1;
}
__interrupt void spiTxFifoIsr(void)
{Uint16 i;for(i=0;i<2;i++){SpiaRegs.SPITXBUF=sdata[i];// Send data}
//
// Increment data buffer contents by 1 for
// the next transmit cycle
//for(i=0;i<2;i++){sdata[i] = sdata[i] + 1;}SpiaRegs.SPIFFTX.bit.TXFFINTCLR=1; // Clear Interrupt flagPieCtrlRegs.PIEACK.all|=0x20;// Issue PIE ACK
}
__interrupt void spiRxFifoIsr(void)
{Uint16 i;for(i=0;i<2;i++){rdata[i]=SpiaRegs.SPIRXBUF;// Read data}for(i=0;i<2;i++)// Check received data{if(rdata[i] != rdata_point+i) error();}rdata_point++;SpiaRegs.SPIFFRX.bit.RXFFOVFCLR=1; // Clear Overflow flagSpiaRegs.SPIFFRX.bit.RXFFINTCLR=1; // Clear Interrupt flagPieCtrlRegs.PIEACK.all|=0x20;// Issue PIE ack
}
//===========================================================================
// No more.
//===========================================================================
Joey Mao：
回复 yaogang Ye:
通讯中断是根据数据的接收或发送，从而使相应的中断标志位置位，而产生中断
通讯过程中接收或发送数据会产生相应的中断，在数据传输完成之后清除中断标志位，等待下一次中断
程序如下所示，请问这个程序是什么时候产生中断的，怎么从main的空循环里跳出到中断服务子程序的，谢谢？
//###########################################################################
//
//! \addtogroup f2803x_example_list
//! <h1>SPI Digital Loop Back with Interrupts(spi_loopback_interrupts)</h1>
//!
//! This program uses the internal loop back test mode of the peripheral.
//! Other then boot mode pin configuration, no other hardware configuration
//! is required. Both interrupts and the SPI FIFOs are used.
//!
//! A stream of data is sent and then compared to the received stream.
//! The sent data looks like this: \n
//! 0000 0001 \n
//! 0001 0002 \n
//! 0002 0003 \n
//! .... \n
//! FFFE FFFF \n
//! FFFF 0000 \n
//! etc.. \n
//! This pattern is repeated forever.
//!
//! \b Watch \b Variables \n
//! - \b sdata , Data to send
//! - \b rdata , Received data
//! - \b rdata_point , Used to keep track of the last position in
//!the receive stream for error checking
//
//###########################################################################
// $TI Release: F2803x C/C++ Header Files and Peripheral Examples V127 $
// $Release Date: March 30, 2013 $
//###########################################################################
#include "DSP28x_Project.h"// Device Headerfile and Examples Include File
// Prototype statements for functions found within this file.
// interrupt void ISRTimer2(void);
__interrupt void spiTxFifoIsr(void);
__interrupt void spiRxFifoIsr(void);
void delay_loop(void);
void spi_fifo_init(void);
void error();
Uint16 sdata[2];// Send data buffer
Uint16 rdata[2];// Receive data buffer
Uint16 rdata_point; // Keep track of where we are// in the data stream to check received data
void main(void)
{Uint16 i;
// Step 1. Initialize System Control:
// PLL, WatchDog, enable Peripheral Clocks
// This example function is found in the DSP2803x_SysCtrl.c file.InitSysCtrl();
// Step 2. Initalize GPIO:
// This example function is found in the DSP2803x_Gpio.c file and
// illustrates how to set the GPIO to it's default state.
// InitGpio(); // Skipped for this example
// Setup only the GP I/O only for SPI-A functionalityInitSpiaGpio();
// Step 3. Initialize PIE vector table:
// Disable and clear all CPU interruptsDINT;IER = 0x0000;IFR = 0x0000;
// Initialize PIE control registers to their default state:
// This function is found in the DSP2803x_PieCtrl.c file.InitPieCtrl();
// Initialize the PIE vector table with pointers to the shell Interrupt
// Service Routines (ISR).
// This will populate the entire table, even if the interrupt
// is not used in this example. This is useful for debug purposes.
// The shell ISR routines are found in DSP2803x_DefaultIsr.c.
// This function is found in DSP2803x_PieVect.c.InitPieVectTable();
// Interrupts that are used in this example are re-mapped to
// ISR functions found within this file.EALLOW; // This is needed to write to EALLOW protected registersPieVectTable.SPIRXINTA = &spiRxFifoIsr;PieVectTable.SPITXINTA = &spiTxFifoIsr;EDIS;// This is needed to disable write to EALLOW protected registers
// Step 4. Initialize all the Device Peripherals:
// This function is found in DSP2803x_InitPeripherals.c
// InitPeripherals(); // Not required for this examplespi_fifo_init();// Initialize the SPI only
// Step 5. User specific code, enable interrupts:
// Initalize the send data bufferfor(i=0; i<2; i++){sdata[i] = i;}rdata_point = 0;
// Enable interrupts required for this examplePieCtrlRegs.PIECTRL.bit.ENPIE = 1;// Enable the PIE blockPieCtrlRegs.PIEIER6.bit.INTx1=1;// Enable PIE Group 6, INT 1PieCtrlRegs.PIEIER6.bit.INTx2=1;// Enable PIE Group 6, INT 2IER=0x20;// Enable CPU INT6EINT;// Enable Global Interrupts
// Step 6. IDLE loop. Just sit and loop forever (optional):for(;;);
}
// Some Useful local functions
void delay_loop()
{longi;for (i = 0; i < 1000000; i++) {}
}
void error(void)
{__asm("ESTOP0"); //Test failed!! Stop!for (;;);
}
void spi_fifo_init()
{
// Initialize SPI FIFO registersSpiaRegs.SPICCR.bit.SPISWRESET=0; // Reset SPISpiaRegs.SPICCR.all=0x001F;//16-bit character, Loopback modeSpiaRegs.SPICTL.all=0x0017;//Interrupt enabled, Master/Slave XMIT enabledSpiaRegs.SPISTS.all=0x0000;SpiaRegs.SPIBRR=0x0063;// Baud rateSpiaRegs.SPIFFTX.all=0xC022;// Enable FIFO's, set TX FIFO level to 2 1100 0000 0010 0010SpiaRegs.SPIFFRX.all=0x0022;// Set RX FIFO level to 2SpiaRegs.SPIFFCT.all=0x00;SpiaRegs.SPIPRI.all=0x0010;SpiaRegs.SPICCR.bit.SPISWRESET=1; // Enable SPISpiaRegs.SPIFFTX.bit.TXFIFO=1;SpiaRegs.SPIFFRX.bit.RXFIFORESET=1;
}
__interrupt void spiTxFifoIsr(void)
{Uint16 i;for(i=0;i<2;i++){SpiaRegs.SPITXBUF=sdata[i];// Send data}
//
// Increment data buffer contents by 1 for
// the next transmit cycle
//for(i=0;i<2;i++){sdata[i] = sdata[i] + 1;}SpiaRegs.SPIFFTX.bit.TXFFINTCLR=1; // Clear Interrupt flagPieCtrlRegs.PIEACK.all|=0x20;// Issue PIE ACK
}
__interrupt void spiRxFifoIsr(void)
{Uint16 i;for(i=0;i<2;i++){rdata[i]=SpiaRegs.SPIRXBUF;// Read data}for(i=0;i<2;i++)// Check received data{if(rdata[i] != rdata_point+i) error();}rdata_point++;SpiaRegs.SPIFFRX.bit.RXFFOVFCLR=1; // Clear Overflow flagSpiaRegs.SPIFFRX.bit.RXFFINTCLR=1; // Clear Interrupt flagPieCtrlRegs.PIEACK.all|=0x20;// Issue PIE ack
}
//===========================================================================
// No more.
//===========================================================================
yaogang Ye：
回复 Joey Mao:
但是在这个例子里，SPI的接受和发送不是在第一次中断产生后，才从主程序调到中断子程序的么？那第一次中断是怎么产生的啊？
程序如下所示，请问这个程序是什么时候产生中断的，怎么从main的空循环里跳出到中断服务子程序的，谢谢？
//###########################################################################
//
//! \addtogroup f2803x_example_list
//! <h1>SPI Digital Loop Back with Interrupts(spi_loopback_interrupts)</h1>
//!
//! This program uses the internal loop back test mode of the peripheral.
//! Other then boot mode pin configuration, no other hardware configuration
//! is required. Both interrupts and the SPI FIFOs are used.
//!
//! A stream of data is sent and then compared to the received stream.
//! The sent data looks like this: \n
//! 0000 0001 \n
//! 0001 0002 \n
//! 0002 0003 \n
//! .... \n
//! FFFE FFFF \n
//! FFFF 0000 \n
//! etc.. \n
//! This pattern is repeated forever.
//!
//! \b Watch \b Variables \n
//! - \b sdata , Data to send
//! - \b rdata , Received data
//! - \b rdata_point , Used to keep track of the last position in
//!the receive stream for error checking
//
//###########################################################################
// $TI Release: F2803x C/C++ Header Files and Peripheral Examples V127 $
// $Release Date: March 30, 2013 $
//###########################################################################
#include "DSP28x_Project.h"// Device Headerfile and Examples Include File
// Prototype statements for functions found within this file.
// interrupt void ISRTimer2(void);
__interrupt void spiTxFifoIsr(void);
__interrupt void spiRxFifoIsr(void);
void delay_loop(void);
void spi_fifo_init(void);
void error();
Uint16 sdata[2];// Send data buffer
Uint16 rdata[2];// Receive data buffer
Uint16 rdata_point; // Keep track of where we are// in the data stream to check received data
void main(void)
{Uint16 i;
// Step 1. Initialize System Control:
// PLL, WatchDog, enable Peripheral Clocks
// This example function is found in the DSP2803x_SysCtrl.c file.InitSysCtrl();
// Step 2. Initalize GPIO:
// This example function is found in the DSP2803x_Gpio.c file and
// illustrates how to set the GPIO to it's default state.
// InitGpio(); // Skipped for this example
// Setup only the GP I/O only for SPI-A functionalityInitSpiaGpio();
// Step 3. Initialize PIE vector table:
// Disable and clear all CPU interruptsDINT;IER = 0x0000;IFR = 0x0000;
// Initialize PIE control registers to their default state:
// This function is found in the DSP2803x_PieCtrl.c file.InitPieCtrl();
// Initialize the PIE vector table with pointers to the shell Interrupt
// Service Routines (ISR).
// This will populate the entire table, even if the interrupt
// is not used in this example. This is useful for debug purposes.
// The shell ISR routines are found in DSP2803x_DefaultIsr.c.
// This function is found in DSP2803x_PieVect.c.InitPieVectTable();
// Interrupts that are used in this example are re-mapped to
// ISR functions found within this file.EALLOW; // This is needed to write to EALLOW protected registersPieVectTable.SPIRXINTA = &spiRxFifoIsr;PieVectTable.SPITXINTA = &spiTxFifoIsr;EDIS;// This is needed to disable write to EALLOW protected registers
// Step 4. Initialize all the Device Peripherals:
// This function is found in DSP2803x_InitPeripherals.c
// InitPeripherals(); // Not required for this examplespi_fifo_init();// Initialize the SPI only
// Step 5. User specific code, enable interrupts:
// Initalize the send data bufferfor(i=0; i<2; i++){sdata[i] = i;}rdata_point = 0;
// Enable interrupts required for this examplePieCtrlRegs.PIECTRL.bit.ENPIE = 1;// Enable the PIE blockPieCtrlRegs.PIEIER6.bit.INTx1=1;// Enable PIE Group 6, INT 1PieCtrlRegs.PIEIER6.bit.INTx2=1;// Enable PIE Group 6, INT 2IER=0x20;// Enable CPU INT6EINT;// Enable Global Interrupts
// Step 6. IDLE loop. Just sit and loop forever (optional):for(;;);
}
// Some Useful local functions
void delay_loop()
{longi;for (i = 0; i < 1000000; i++) {}
}
void error(void)
{__asm("ESTOP0"); //Test failed!! Stop!for (;;);
}
void spi_fifo_init()
{
// Initialize SPI FIFO registersSpiaRegs.SPICCR.bit.SPISWRESET=0; // Reset SPISpiaRegs.SPICCR.all=0x001F;//16-bit character, Loopback modeSpiaRegs.SPICTL.all=0x0017;//Interrupt enabled, Master/Slave XMIT enabledSpiaRegs.SPISTS.all=0x0000;SpiaRegs.SPIBRR=0x0063;// Baud rateSpiaRegs.SPIFFTX.all=0xC022;// Enable FIFO's, set TX FIFO level to 2 1100 0000 0010 0010SpiaRegs.SPIFFRX.all=0x0022;// Set RX FIFO level to 2SpiaRegs.SPIFFCT.all=0x00;SpiaRegs.SPIPRI.all=0x0010;SpiaRegs.SPICCR.bit.SPISWRESET=1; // Enable SPISpiaRegs.SPIFFTX.bit.TXFIFO=1;SpiaRegs.SPIFFRX.bit.RXFIFORESET=1;
}
__interrupt void spiTxFifoIsr(void)
{Uint16 i;for(i=0;i<2;i++){SpiaRegs.SPITXBUF=sdata[i];// Send data}
//
// Increment data buffer contents by 1 for
// the next transmit cycle
//for(i=0;i<2;i++){sdata[i] = sdata[i] + 1;}SpiaRegs.SPIFFTX.bit.TXFFINTCLR=1; // Clear Interrupt flagPieCtrlRegs.PIEACK.all|=0x20;// Issue PIE ACK
}
__interrupt void spiRxFifoIsr(void)
{Uint16 i;for(i=0;i<2;i++){rdata[i]=SpiaRegs.SPIRXBUF;// Read data}for(i=0;i<2;i++)// Check received data{if(rdata[i] != rdata_point+i) error();}rdata_point++;SpiaRegs.SPIFFRX.bit.RXFFOVFCLR=1; // Clear Overflow flagSpiaRegs.SPIFFRX.bit.RXFFINTCLR=1; // Clear Interrupt flagPieCtrlRegs.PIEACK.all|=0x20;// Issue PIE ack
}
//===========================================================================
// No more.
//===========================================================================
Joey Mao：
回复 yaogang Ye:
中断程序是独立的，在完成相关中断初始化之后，可以说这部分就处于等待状态，如果满足中断产生的条件，即有数据接收和发送，则会产生中断
