ssi.zip_ssi spi

//***************************************************************************** // // soft_spi_master.c - Example demonstrating how to configure SoftSSI. // // Copyright (c) 2010 Texas Instruments Incorporated. All rights reserved. // Software License Agreement // // Texas Instruments (TI) is supplying this software for use solely and // exclusively on TI's microcontroller products. The software is owned by // TI and/or its suppliers, and is protected under applicable copyright // laws. You may not combine this software with "viral" open-source // software in order to form a larger program. // // THIS SOFTWARE IS PROVIDED "AS IS" AND WITH ALL FAULTS. // NO WARRANTIES, WHETHER EXPRESS, IMPLIED OR STATUTORY, INCLUDING, BUT // NOT LIMITED TO, IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR // A PARTICULAR PURPOSE APPLY TO THIS SOFTWARE. TI SHALL NOT, UNDER ANY // CIRCUMSTANCES, BE LIABLE FOR SPECIAL, INCIDENTAL, OR CONSEQUENTIAL // DAMAGES, FOR ANY REASON WHATSOEVER. // // This is part of revision 6288 of the Stellaris Firmware Development Package. // //***************************************************************************** #include <string.h> #include "inc/hw_memmap.h" #include "inc/hw_types.h" #include "driverlib/gpio.h" #include "driverlib/sysctl.h" #include "driverlib/systick.h" #include "utils/softssi.h" #include "utils/uartstdio.h" //***************************************************************************** // //! \addtogroup ssi_examples_list //! <h1>SoftSSI Master (soft_spi_master)</h1> //! //! This example shows how to configure the SoftSSI module. The code will send //! three characters on the master Tx then polls the receive FIFO until 3 //! characters are received on the master Rx. //! //! This example uses the following peripherals and I/O signals. You must //! review these and change as needed for your own board: //! - GPIO Port A peripheral (for SoftSSI pins) //! - SoftSSICLK - PA2 //! - SoftSSIFss - PA3 //! - SoftSSIRx - PA4 //! - SoftSSITx - PA5 //! //! The following UART signals are configured only for displaying console //! messages for this example. These are not required for operation of //! SoftSSI. //! - UART0 peripheral //! - GPIO Port A peripheral (for UART0 pins) //! - UART0RX - PA0 //! - UART0TX - PA1 //! //! This example uses the following interrupt handlers. To use this example //! in your own application you must add these interrupt handlers to your //! vector table. //! - SysTickIntHandler //! //! \note This example provide the same functionality using the same pins as //! the spi_master example. As such, it can be used as a guide for how to //! convert code which uses hardware SSI to the SoftSSI module. // //***************************************************************************** //***************************************************************************** // // Number of bytes to send and receive. // //***************************************************************************** #define NUM_SSI_DATA 3 //***************************************************************************** // // The persistent state of the SoftSSI peripheral. // //***************************************************************************** tSoftSSI g_sSoftSSI; //***************************************************************************** // // The data buffer that is used as the transmit FIFO. The size of this buffer // can be increased or decreased as required to match the transmit buffering // requirements of your application. // //***************************************************************************** unsigned short g_pusTxBuffer[16]; //***************************************************************************** // // The data buffer that is used as the receive FIFO. The size of this buffer // can be increased or decreased as required to match the receive buffering // requirements of your application. // //***************************************************************************** unsigned short g_pusRxBuffer[16]; //***************************************************************************** // // This function sets up UART0 to be used for a console to display information // as the example is running. // //***************************************************************************** void InitConsole(void) { // // Enable GPIO port A which is used for UART0 pins. // TODO: change this to whichever GPIO port you are using. // SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOA); // // Configure the pin muxing for UART0 functions on port A0 and A1. // This step is not necessary if your part does not support pin muxing. // TODO: change this to select the port/pin you are using. // GPIOPinConfigure(GPIO_PA0_U0RX); GPIOPinConfigure(GPIO_PA1_U0TX); // // Select the alternate (UART) function for these pins. // TODO: change this to select the port/pin you are using. // GPIOPinTypeUART(GPIO_PORTA_BASE, GPIO_PIN_0 | GPIO_PIN_1); // // Initialize the UART for console I/O. // UARTStdioInit(0); } //***************************************************************************** // // The interrupt handler for the SysTick interrupt. // //***************************************************************************** void SysTickIntHandler(void) { // // Call the SoftSSI timer tick. // SoftSSITimerTick(&g_sSoftSSI); } //***************************************************************************** // // Configure SoftSSI in SPI mode 0. This example will send out 3 bytes of // data, then wait for 3 bytes of data to come in. This will all be done using // the polling method. // //***************************************************************************** int main(void) { unsigned long ulDataTx[NUM_SSI_DATA]; unsigned long ulDataRx[NUM_SSI_DATA]; unsigned long ulindex; // // Set the clocking to run directly from the external crystal/oscillator. // TODO: The SYSCTL_XTAL_ value must be changed to match the value of the // crystal on your board. // SysCtlClockSet(SYSCTL_SYSDIV_1 | SYSCTL_USE_OSC | SYSCTL_OSC_MAIN | SYSCTL_XTAL_16MHZ); // // Set up the serial console to use for displaying messages. This is // just for this example program and is not needed for SSI operation. // InitConsole(); // // Display the setup on the console. // UARTprintf("SoftSSI ->\n"); UARTprintf(" Data: 8-bit\n\n"); // // For this example SoftSSI is used with PortA[5:2]. The actual port and // pins used may be different on your design based on the set of GPIO pins // available. GPIO port A needs to be enabled so these pins can be used. // TODO: change this to whichever GPIO port you are using. // SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOA); // // Configure the SoftSSI module. The size of the FIFO buffers can be // changed to accommodate the requirements of your application. The GPIO // pins utilized can also be changed. // The pins are assigned as follows: // PA2 - SoftSSICLK // PA3 - SoftSSIFss // PA4 - SoftSSIRx // PA5 - SoftSSITx // TODO: change this to select the port/pin you are using. // TODO: change the buffer sizes to match your requirements. // memset(&g_sSoftSSI, 0, sizeof(g_sSoftSSI)); SoftSSIClkGPIOSet(&g_sSoftSSI, GPIO_PORTA_BASE, GPIO_PIN_2); SoftSSIFssGPIOSet(&g_sSoftSSI, GPIO_PORTA_BASE, GPIO_PIN_3); SoftSSIRxGPIOSet(&g_sSoftSSI, GPIO_PORTA_BASE, GPIO_PIN_4); SoftSSITxGPIOSet(&g_sSoftSSI, GPIO_PORTA_BASE, GPIO_PIN_5); SoftSSIRxBufferSet(&g_sSoftSSI, g_pusRxBuffer, sizeo