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Defines | |
#define | BOOTLOADER_SECTION __attribute__ ((section (".bootloader"))) |
#define | boot_spm_interrupt_enable() (__SPM_REG |= (uint8_t)_BV(SPMIE)) |
#define | boot_spm_interrupt_disable() (__SPM_REG &= (uint8_t)~_BV(SPMIE)) |
#define | boot_is_spm_interrupt() (__SPM_REG & (uint8_t)_BV(SPMIE)) |
#define | boot_rww_busy() (__SPM_REG & (uint8_t)_BV(__COMMON_ASB)) |
#define | boot_spm_busy() (__SPM_REG & (uint8_t)_BV(__SPM_ENABLE)) |
#define | boot_spm_busy_wait() do{}while(boot_spm_busy()) |
#define | GET_LOW_FUSE_BITS (0x0000) |
#define | GET_LOCK_BITS (0x0001) |
#define | GET_EXTENDED_FUSE_BITS (0x0002) |
#define | GET_HIGH_FUSE_BITS (0x0003) |
#define | boot_lock_fuse_bits_get(address) |
#define | boot_signature_byte_get(addr) |
#define | boot_page_fill(address, data) __boot_page_fill_normal(address, data) |
#define | boot_page_erase(address) __boot_page_erase_normal(address) |
#define | boot_page_write(address) __boot_page_write_normal(address) |
#define | boot_rww_enable() __boot_rww_enable() |
#define | boot_lock_bits_set(lock_bits) __boot_lock_bits_set(lock_bits) |
#define | boot_page_fill_safe(address, data) |
#define | boot_page_erase_safe(address) |
#define | boot_page_write_safe(address) |
#define | boot_rww_enable_safe() |
#define | boot_lock_bits_set_safe(lock_bits) |
#include <avr/io.h> #include <avr/boot.h>
The macros in this module provide a C language interface to the bootloader support functionality of certain AVR processors. These macros are designed to work with all sizes of flash memory.
Global interrupts are not automatically disabled for these macros. It is left up to the programmer to do this. See the code example below. Also see the processor datasheet for caveats on having global interrupts enabled during writing of the Flash.
#include <inttypes.h> #include <avr/interrupt.h> #include <avr/pgmspace.h> void boot_program_page (uint32_t page, uint8_t *buf) { uint16_t i; uint8_t sreg; // Disable interrupts. sreg = SREG; cli(); eeprom_busy_wait (); boot_page_erase (page); boot_spm_busy_wait (); // Wait until the memory is erased. for (i=0; i<SPM_PAGESIZE; i+=2) { // Set up little-endian word. uint16_t w = *buf++; w += (*buf++) << 8; boot_page_fill (page + i, w); } boot_page_write (page); // Store buffer in flash page. boot_spm_busy_wait(); // Wait until the memory is written. // Reenable RWW-section again. We need this if we want to jump back // to the application after bootloading. boot_rww_enable (); // Re-enable interrupts (if they were ever enabled). SREG = sreg; }
#define boot_is_spm_interrupt | ( | ) | (__SPM_REG & (uint8_t)_BV(SPMIE)) |
Check if the SPM interrupt is enabled.
#define boot_lock_bits_set | ( | lock_bits | ) | __boot_lock_bits_set(lock_bits) |
Set the bootloader lock bits.
lock_bits | A mask of which Boot Loader Lock Bits to set. |
For example, to disallow the SPM instruction from writing to the Boot Loader memory section of flash, you would use this macro as such:
boot_lock_bits_set (_BV (BLB11));
#define boot_lock_bits_set_safe | ( | lock_bits | ) |
do { \ boot_spm_busy_wait(); \ eeprom_busy_wait(); \ boot_lock_bits_set (lock_bits); \ } while (0)
Same as boot_lock_bits_set() except waits for eeprom and spm operations to complete before setting the lock bits.
#define boot_lock_fuse_bits_get | ( | address | ) |
(__extension__({ \ uint8_t __result; \ __asm__ __volatile__ \ ( \ "sts %1, %2\n\t" \ "lpm %0, Z\n\t" \ : "=r" (__result) \ : "i" (_SFR_MEM_ADDR(__SPM_REG)), \ "r" ((uint8_t)(__BOOT_LOCK_BITS_SET)), \ "z" ((uint16_t)(address)) \ ); \ __result; \ }))
Read the lock or fuse bits at address
.
Parameter address
can be any of GET_LOW_FUSE_BITS, GET_LOCK_BITS, GET_EXTENDED_FUSE_BITS, or GET_HIGH_FUSE_BITS.
#define boot_page_erase | ( | address | ) | __boot_page_erase_normal(address) |
Erase the flash page that contains address.
#define boot_page_erase_safe | ( | address | ) |
do { \ boot_spm_busy_wait(); \ eeprom_busy_wait(); \ boot_page_erase (address); \ } while (0)
Same as boot_page_erase() except it waits for eeprom and spm operations to complete before erasing the page.
#define boot_page_fill | ( | address, | |
data | |||
) | __boot_page_fill_normal(address, data) |
Fill the bootloader temporary page buffer for flash address with data word.
#define boot_page_fill_safe | ( | address, | |
data | |||
) |
do { \ boot_spm_busy_wait(); \ eeprom_busy_wait(); \ boot_page_fill(address, data); \ } while (0)
Same as boot_page_fill() except it waits for eeprom and spm operations to complete before filling the page.
#define boot_page_write | ( | address | ) | __boot_page_write_normal(address) |
Write the bootloader temporary page buffer to flash page that contains address.
#define boot_page_write_safe | ( | address | ) |
do { \ boot_spm_busy_wait(); \ eeprom_busy_wait(); \ boot_page_write (address); \ } while (0)
Same as boot_page_write() except it waits for eeprom and spm operations to complete before writing the page.
#define boot_rww_busy | ( | ) | (__SPM_REG & (uint8_t)_BV(__COMMON_ASB)) |
Check if the RWW section is busy.
#define boot_rww_enable | ( | ) | __boot_rww_enable() |
Enable the Read-While-Write memory section.
#define boot_rww_enable_safe | ( | ) |
do { \ boot_spm_busy_wait(); \ eeprom_busy_wait(); \ boot_rww_enable(); \ } while (0)
Same as boot_rww_enable() except waits for eeprom and spm operations to complete before enabling the RWW mameory.
#define boot_signature_byte_get | ( | addr | ) |
(__extension__({ \ uint8_t __result; \ __asm__ __volatile__ \ ( \ "sts %1, %2\n\t" \ "lpm %0, Z" "\n\t" \ : "=r" (__result) \ : "i" (_SFR_MEM_ADDR(__SPM_REG)), \ "r" ((uint8_t)(__BOOT_SIGROW_READ)), \ "z" ((uint16_t)(addr)) \ ); \ __result; \ }))
Read the Signature Row byte at address
. For some MCU types, this function can also retrieve the factory-stored oscillator calibration bytes.
Parameter address
can be 0-0x1f as documented by the datasheet.
#define boot_spm_busy | ( | ) | (__SPM_REG & (uint8_t)_BV(__SPM_ENABLE)) |
Check if the SPM instruction is busy.
#define boot_spm_busy_wait | ( | ) | do{}while(boot_spm_busy()) |
Wait while the SPM instruction is busy.
#define boot_spm_interrupt_disable | ( | ) | (__SPM_REG &= (uint8_t)~_BV(SPMIE)) |
Disable the SPM interrupt.
#define boot_spm_interrupt_enable | ( | ) | (__SPM_REG |= (uint8_t)_BV(SPMIE)) |
Enable the SPM interrupt.
#define BOOTLOADER_SECTION __attribute__ ((section (".bootloader"))) |
Used to declare a function or variable to be placed into a new section called .bootloader. This section and its contents can then be relocated to any address (such as the bootloader NRWW area) at link-time.
#define GET_EXTENDED_FUSE_BITS (0x0002) |
address to read the extended fuse bits, using boot_lock_fuse_bits_get
#define GET_HIGH_FUSE_BITS (0x0003) |
address to read the high fuse bits, using boot_lock_fuse_bits_get
#define GET_LOCK_BITS (0x0001) |
address to read the lock bits, using boot_lock_fuse_bits_get
#define GET_LOW_FUSE_BITS (0x0000) |
address to read the low fuse bits, using boot_lock_fuse_bits_get