C8051f020spI例子程序

//----------------------------------------------------------------------------- // F02x_SPI0_Master.c //----------------------------------------------------------------------------- // Copyright 2006 Silicon Laboratories, Inc. // http://www.silabs.com // // Program Description: // // This program configures a C8051F02x as a 4-wire SPI Single Master. // // The SPI clock in this example is limited to 320 kHz when used with the // SPI0_Slave code example. During a SPI_Read, the slave needs some time to // interpret the command and write the appropriate data to the SPI0DAT // register, and the slave no longer has enough time to complete the // SPI_READ_BUFFER command with a clock greater than 320 kHz. For faster SPI // clocks, a dummy byte between the command and the first byte of Read data // will be required. // // This example is intended to be used with the SPI0_Slave example. // // Pinout: // // P0.0 - SPI SCK (digital output, push-pull) // P0.1 - SPI MISO (digital input, open-drain) // P0.2 - SPI MOSI (digital output, push-pull) // P0.3 - SPI NSS (digital input, open-drain) // // P0.7 - SLAVE_SEL (digital output, push-pull) This pin should be routed // to NSS on the slave // // P1.6 - LED (digital output, push-pull) // // all other port pins unused. // // // How To Test: // // 1) Download the code to a F020-TB that is connected as above to // another device running the SPI0_Slave code. // 2) Verify that the J3 jumper is populated. // 3) Run the code. // 4) If the communication passes, the LEDs on both the Master and Slave // boards will blink slowly. If it fails, the LEDs will be OFF. // // // Target: C8051F02x // Tool chain: Keil C51 7.50 / Keil EVAL C51 // Command Line: None // // Release 1.0 // -Initial Revision (TP) // -14 DEC 2006 // //----------------------------------------------------------------------------- // Includes //----------------------------------------------------------------------------- #include <C8051F020.h> // SFR declarations //----------------------------------------------------------------------------- // Global Constants //----------------------------------------------------------------------------- #define SYSCLK 16000000 // Internal oscillator frequency in Hz #define SPI_CLOCK 320000 // Maximum SPI clock // The SPI clock is a maximum of 320 kHz // when this example is used with // the SPI0_Slave code example. #define MAX_BUFFER_SIZE 8 // Maximum buffer Master will send // Instruction Set #define SLAVE_LED_ON 0x01 // Turn the Slave LED on #define SLAVE_LED_OFF 0x02 // Turn the Slave LED off #define SPI_WRITE 0x04 // Send a byte from the Master to the // Slave #define SPI_READ 0x08 // Send a byte from the Slave to the // Master #define SPI_WRITE_BUFFER 0x10 // Send a series of bytes from the // Master to the Slave #define SPI_READ_BUFFER 0x20 // Send a series of bytes from the Slave // to the Master #define ERROR_OCCURRED 0x40 // Indicator for the Slave to tell the // Master an error occurred sbit LED = P1^6; // LED='1' means ON sbit SLAVE_SEL = P0^7; // Slave select pin (NSS) //----------------------------------------------------------------------------- // Global Variables //----------------------------------------------------------------------------- unsigned char SPI_Data = 0xA5; unsigned char SPI_Data_Array[MAX_BUFFER_SIZE] = {0}; bit Error_Flag = 0; unsigned char Command = 0x00; bit Transfer_In_Progress = 0; //----------------------------------------------------------------------------- // Function Prototypes //----------------------------------------------------------------------------- void Watchdog_Init (void); void Oscillator_Init (void); void Port_Init (void); void SPI0_Init (void); void Init_Device (void); void SPI_LED_On (void); void SPI_LED_Off (void); void SPI_Byte_Write (void); void SPI_Byte_Read (void); void SPI_Array_Write (void); void SPI_Array_Read (void); void Delay (void); void Short_Delay (void); //----------------------------------------------------------------------------- // main() Routine //----------------------------------------------------------------------------- void main (void) { unsigned char test_value = 0x55; unsigned char test_array[MAX_BUFFER_SIZE] = {1,2,3,4,5,6,7,8}; unsigned char i; Init_Device (); // Initializes hardware peripherals EA = 1; // Enable global interrupts LED = 0; // TEST BEGIN -------------------------------------------------------------- SPI_Data = test_value; // Write a value SPI_Byte_Write (); while (Transfer_In_Progress); // Wait until the Write transfer has // finished // Read the same value back SPI_Data = 0x00; SPI_Byte_Read (); while (Transfer_In_Progress); // Wait until the Write transfer has // finished // Check if the sent value and returned value match if (SPI_Data != test_value) { Error_Flag = 1; } // Copy test_array into SPI_Data_Array for (i = 0; i < MAX_BUFFER_SIZE; i++) { SPI_Data_Array[i] = test_array[i]; } // Send the array to the slave SPI_Array_Write (); while (Transfer_In_Progress); // Wait until the Write transfer has // finished // Clear SPI_Data_Array for the SPI_Buffer_Read function for (i = 0; i < MAX_BUFFER_SIZE; i++) { SPI_Data_Array[i] = 0; } // Read the array back from the slave SPI_Array_Read (); while (Transfer_In_Progress); // Wait until the Write transfer has // finished // Check if the received array matches the sent array for (i = 0; i < MAX_BUFFER_SIZE; i++) { if (SPI_Data_Array[i] != test_array[i]) { Error_Flag = 1; } } // END OF TEST ------------------------------------------------------------- while (1) { // If no error has occurred, blink the LEDs on the Master and Slave // boards if (Error_Flag == 0) { LED = 1; SPI_LED_On (); while (Transfer_In_Progress); // Wait until the Write transfer has // finished Delay (); SPI_LED_Off (); LED = 0; while (Transfer_In_Progress); // Wait until the Write transfer has // finished Delay (); } }; } //----------------------------------------------------------------------------- // Initialization Subroutines //----------------------------------------------------------------------------- //----------------------------------------------------------------------------- // Watchdog_Init //----------------------------------------------------------------------------- // // Return Value : None // Parameters : None // // This function disables the watchdog timer. // //----------------------------------------------------------------------------- void Watchdog_Init (void) { WDTCN = 0xDE; // Disable the Watchdog Timer WDTCN = 0xAD; } //--------------------------------------------