These are the examples provided for [[/users/frank26080115/libraries/LPC1700CMSIS_Lib/]] Note, the entire "program" is not compilable!
Diff: Cortex-M3/Bit-banding/bitband.c
- Revision:
- 0:bf7b9fba3924
diff -r 000000000000 -r bf7b9fba3924 Cortex-M3/Bit-banding/bitband.c --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/Cortex-M3/Bit-banding/bitband.c Sun Mar 20 05:38:56 2011 +0000 @@ -0,0 +1,209 @@ +/***********************************************************************//** + * @file bitband.c + * @purpose This example used to test bit-banding feature of Cortex-M3 + * processor. + * @version 2.0 + * @date 21. May. 2010 + * @author NXP MCU SW Application Team + *--------------------------------------------------------------------- + * Software that is described herein is for illustrative purposes only + * which provides customers with programming information regarding the + * products. This software is supplied "AS IS" without any warranties. + * NXP Semiconductors assumes no responsibility or liability for the + * use of the software, conveys no license or title under any patent, + * copyright, or mask work right to the product. NXP Semiconductors + * reserves the right to make changes in the software without + * notification. NXP Semiconductors also make no representation or + * warranty that such application will be suitable for the specified + * use without further testing or modification. + **********************************************************************/ +#include "lpc17xx_libcfg.h" +#include "debug_frmwrk.h" + +/* Example group ----------------------------------------------------------- */ +/** @defgroup Cortex_M3_Bit_banding Bit-banding + * @ingroup Cortex_M3_Examples + * @{ + */ + +/************************** PRIVATE DEFINTIONS*************************/ +/* The processor memory map includes two bit-band regions. These occupy the lowest + * 1MB of the SRAM and peripheral memory regions respectively. + * + SRAM: Bit-band region: 0x20000000 - 0x20100000 + * Bit-band alias: 0x22000000 - 0x23FFFFFF + * + PERI: Bit-band region: 0x40000000 - 0x40100000 + * Bit-band alias: 0x42000000 - 0x43FFFFFF + * The mapping formula: + * bit_word_offset = (byte_offset * 32) + (bit_number * 4) + * bit_word_address = bit_band_base + bit_word_offset + * where: + * + bit_word_offset: the position of the target bit in the bit-band memory region + * + bit_word_addr: the address of the word in the alias memory region that maps to the target bit + * + bit_band_base: the starting address of the alias region + * + byte_offset: the number of byte in the bit-band region that contains the targeted bit + * + bit_number: is the bit position (0-7) of the targeted bit + * + * Note: The fact, the SRAM on LPC1768 just available in two ranges: + * + 0x2007C000 - 0x2007FFFF: for SRAM - bank 0 + * + 0x20080000 - 0x20083FFF: for SRAM - bank 1 + * (And one range for GPIO peripheral but assigned in SRAM ranges: 0x2009C000 - 0x2009FFFF) + */ + +/* Bit band SRAM definitions */ +#define BITBAND_SRAM_REF 0x20000000 +#define BITBAND_SRAM_BASE 0x22000000 + +#define BITBAND_SRAM(a,b) ((BITBAND_SRAM_BASE + ((a-BITBAND_SRAM_REF)<<5) + (b<<2))) // Convert SRAM address + +/* Bit band PERIPHERAL definitions */ +#define BITBAND_PERI_REF 0x40000000 +#define BITBAND_PERI_BASE 0x42000000 + +#define BITBAND_PERI(a,b) ((BITBAND_PERI_BASE + ((a-BITBAND_PERI_REF)<<5) + (b<<2))) // Convert PERI address + +/* Basic bit band function definitions */ +#define BITBAND_SRAM_ClearBit(a,b) (*(volatile uint32_t *) (BITBAND_SRAM(a,b)) = 0) +#define BITBAND_SRAM_SetBit(a,b) (*(volatile uint32_t *) (BITBAND_SRAM(a,b)) = 1) +#define BITBAND_SRAM_GetBit(a,b) (*(volatile uint32_t *) (BITBAND_SRAM(a,b))) + +#define BITBAND_PERI_ClearBit(a,b) (*(volatile uint32_t *) (BITBAND_PERI(a,b)) = 0) +#define BITBAND_PERI_SetBit(a,b) (*(volatile uint32_t *) (BITBAND_PERI(a,b)) = 1) +#define BITBAND_PERI_GetBit(a,b) (*(volatile uint32_t *) (BITBAND_PERI(a,b))) + +/* Variable address in SRAM + * should be in one of two range: + * + 0x2007C000 - 0x20083FFF: for SRAM + * + 0x20080000 - 0x20083FFF: for GPIO + */ +#define VAR_ADDRESS 0x2007C000 +#define VAR_BIT 3 //Bit 3 + +/* Peripheral address + * should be in range: 0x40000000 - 0x40100000 + */ +#define PERI_ADDRESS 0x40020000 // SPI Control Register (S0SPCR) +#define PERI_BIT 5 //bit 5 - Master mode select + +/************************** PRIVATE VARIABLES *************************/ +uint8_t menu[]= + "********************************************************************************\n\r" + "Hello NXP Semiconductors \n\r" + "Bit-banding demo \n\r" + "\t - MCU: LPC17xx \n\r" + "\t - Core: ARM CORTEX-M3 \n\r" + "\t - Communicate via: UART0 - 115200 bps \n\r" + "This example used to test Bit-banding feature of Cortex-M3 processor\n\r" + "********************************************************************************\n\r"; + +/*-------------------------MAIN FUNCTION------------------------------*/ +/*********************************************************************//** + * @brief c_entry: main function + * @param[in] none + * @return int + **********************************************************************/ +int c_entry(void) { /* Main Program */ + + uint32_t temp; + + /* Initialize debug via UART0 + * 115200bps + * 8 data bit + * No parity + * 1 stop bit + * No flow control + */ + debug_frmwrk_init(); + //print menu + _DBG(menu); + + /* test Bit-banding SRAM first --------------------------------------------------------- */ + _DBG_("Test bit-band SRAM... "); + + //read variable at VAR_ADDRESS + temp = (*(volatile uint32_t *)(VAR_ADDRESS)); + //print temp value + _DBG("The value at address "); _DBH32(VAR_ADDRESS); _DBG(": "); + _DBH32(temp); _DBG_(""); + + /* Use bitband function to read VAR_BIT value */ + temp = BITBAND_SRAM_GetBit(VAR_ADDRESS,VAR_BIT); + _DBG("Use bit-band function to get value at bit 3: ");_DBG_(""); + _DBH32(temp); _DBG_(""); + + /* clear bit */ + BITBAND_SRAM_ClearBit(VAR_ADDRESS,VAR_BIT); + /* re-read temp value */ + temp = (*(volatile uint32_t *)(VAR_ADDRESS)); + _DBG("Value after clear bit 3 value by using bit-band function: ");_DBG_(""); + _DBH32(temp); _DBG_(""); + + /* Set bit */ + BITBAND_SRAM_SetBit(VAR_ADDRESS,VAR_BIT); + /* re-read temp value */ + temp = (*(volatile uint32_t *)(VAR_ADDRESS)); + _DBG("Value after set bit 3 value by using bit-band function: ");_DBG_(""); + _DBH32(temp); _DBG_(""); + _DBG_(""); + + /* Then, test Bit-banding PERI --------------------------------------------------------- */ + _DBG_("Test bit-band PERIPHERAL... "); + + LPC_SPI->SPCR =(1<<5)|(1<<3)|(10<<8); + + /* Read the current value of peripheral register */ + temp = (*(volatile uint32_t *)(PERI_ADDRESS)); + _DBG("The value of peripheral register at "); _DBH32(PERI_ADDRESS); _DBG(": ");_DBG_(""); + _DBH32(temp); _DBG_(""); + + /* Use bitband function to read VAR_BIT value */ + temp = BITBAND_PERI_GetBit(PERI_ADDRESS,PERI_BIT); + _DBG("Use bit-band function to get value at bit 5: ");_DBG_(""); _DBH32(temp); _DBG_(""); + + /* clear bit */ + BITBAND_PERI_ClearBit(PERI_ADDRESS,PERI_BIT); + /* re-read temp value */ + temp = (*(volatile uint32_t *)(PERI_ADDRESS)); + _DBG("Peripheral register after clear bit 5 value by using bit-band function: ");_DBG_(""); + _DBH32(temp); _DBG_(""); + + /* Set bit */ + BITBAND_PERI_SetBit(PERI_ADDRESS,PERI_BIT); + /* re-read temp value */ + temp = (*(volatile uint32_t *)(PERI_ADDRESS)); + _DBG("Peripheral register after set bit 5 value by using bit-band function: ");_DBG_(""); + _DBH32(temp); _DBG_(""); + + while (1); + return 0; +} + +/* With ARM and GHS toolsets, the entry point is main() - this will + allow the linker to generate wrapper code to setup stacks, allocate + heap area, and initialize and copy code and data segments. For GNU + toolsets, the entry point is through __start() in the crt0_gnu.asm + file, and that startup code will setup stacks and data */ +int main(void) { + return c_entry(); +} + +#ifdef DEBUG +/******************************************************************************* + * @brief Reports the name of the source file and the source line number + * where the CHECK_PARAM error has occurred. + * @param[in] file Pointer to the source file name + * @param[in] line assert_param error line source number + * @return None + *******************************************************************************/ +void check_failed(uint8_t *file, uint32_t line) { + /* User can add his own implementation to report the file name and line number, + ex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */ + + /* Infinite loop */ + while (1) + ; +} +#endif + +/* + * @} + */