zhongduan.rar_visual c

//----------------------------------------------------------------------------- // F02x_External_Interrupts.c //----------------------------------------------------------------------------- // Copyright 2007 Silicon Laboratories, Inc. // http://www.silabs.com // // Program Description: // // This software shows the necessary configuration to use External Interrupt 0 // (/INT0) or External Interrupt 1 (/INT1) as an interrupt source. The code // executes the initialization routines and then spins in an infinite while() // loop. If the button P3.7 (on the target board) is pressed, then the // edge-triggered /INT0 input on P0.0 will cause an interrupt and toggle the // LED. // // Pinout: // // P0.0 - /INT0 // P0.1 - /INT1 // // P1.6 - LED // // P3.7 - SWITCH // // How To Test: // // 1) Compile and download code to a 'F02x target board. // 2) On the target board, connect the switch side of J1 to either P0.0 for // /INT0 or P0.1 for /INT1. // 3) Verify the J3 jumper is in place. // 4) Verify the J6 and J9 jumpers are removed. // 5) Press the P3.7 switch. Every time the switch is pressed, the P1.6 LED // should toggle. // // Target: C8051F02x // Tool chain: Keil C51 7.50 / Keil EVAL C51 // Command Line: None // // // Release 1.0 // -Initial Revision (SM) // -19 JUN 2007 // //----------------------------------------------------------------------------- // Include Files //----------------------------------------------------------------------------- #include <C8051F020.h> //----------------------------------------------------------------------------- // Global Constants //----------------------------------------------------------------------------- #define SYSCLK (22118400L) sbit LED = P1^6; // Green Led sbit SWITCH = P3^7; // Push-button switch on board //----------------------------------------------------------------------------- // Function Prototypes //----------------------------------------------------------------------------- void Oscillator_Init (void); // Configure the system clock void Port_Init (void); // Configure the Crossbar and GPIO void Ext_Interrupt_Init (void); // Configure External Interrupts (/INT0 // and /INT1) //----------------------------------------------------------------------------- // MAIN Routine //----------------------------------------------------------------------------- void main (void) { WDTCN = 0xDE; // Disable Watchdog timer WDTCN = 0xAD; Oscillator_Init(); // Initialize the system clock Port_Init (); // Initialize crossbar and GPIO Ext_Interrupt_Init(); // Initialize External Interrupts EA = 1; while(1); // Infinite while loop waiting for // an interrupt from /INT0 or /INT1 } //----------------------------------------------------------------------------- // Initialization Subroutines //----------------------------------------------------------------------------- //----------------------------------------------------------------------------- // OSCILLATOR_Init //----------------------------------------------------------------------------- // // Return Value : None // Parameters : None // // This function initializes the system clock to use the external 22.1184MHz // crystal. // //----------------------------------------------------------------------------- void OSCILLATOR_Init (void) { int i; // Software timer OSCICN |= 0x80; // Enable the missing clock detector // Initialize external crystal oscillator to use 22.1184 MHz crystal OSCXCN = 0x67; // Enable external crystal osc. for (i=0; i < 256; i++); // Wait at least 1ms while (!(OSCXCN & 0x80)); // Wait for crystal osc to settle OSCICN |= 0x08; // Select external clock source OSCICN &= ~0x04; // Disable the internal osc. } //----------------------------------------------------------------------------- // Port_Init //----------------------------------------------------------------------------- // // Return Value : None // Parameters : None // // This function configures the crossbar and GPIO ports. // // Pinout: // // P0.0 - digital open-drain /INT0 // P0.1 - digital open-drain /INT1 // // P1.6 - digital push-pull LED // // P3.7 - digital open-drain SWITCH // //----------------------------------------------------------------------------- void Port_Init (void) { XBR0 = 0x00; XBR1 = 0x14; // No peripherals selected XBR2 = 0x40; // Enable crossbar and weak pullups P1MDOUT = 0x40; // LED is push-pull a output } //----------------------------------------------------------------------------- // Ext_Interrupt_Init //----------------------------------------------------------------------------- // // Return Value : None // Parameters : None // // This function configures and enables /INT0 and /INT1 (External Interrupts) // as negative edge-triggered. // //----------------------------------------------------------------------------- void Ext_Interrupt_Init (void) { TCON = 0x05; // /INT 0 and /INT 1 are falling edge // triggered EX0 = 1; // Enable /INT0 interrupts EX1 = 1; // Enable /INT1 interrupts } //----------------------------------------------------------------------------- // Interrupt Service Routines //----------------------------------------------------------------------------- //----------------------------------------------------------------------------- // /INT0 ISR //----------------------------------------------------------------------------- // // Whenever a negative edge appears on P0.0, the LED is toggled. // The interrupt pending flag is automatically cleared by vectoring to the ISR // //----------------------------------------------------------------------------- void INT0_ISR (void) interrupt 0 { LED = !LED; } //----------------------------------------------------------------------------- // /INT1 ISR //----------------------------------------------------------------------------- // // Whenever a negative edge appears on P0.1, the LED is toggled. // The interrupt pending flag is automatically cleared by vectoring to the ISR // //----------------------------------------------------------------------------- void INT1_ISR (void) interrupt 2 { LED = !LED; } //----------------------------------------------------------------------------- // End Of File //-----------------------------------------------------------------------------