+ #elif defined(BOOTLOADER_USBASP)
+ // Taken with permission of Stephan Baerwolf from https://github.com/tinyusbboard/API/blob/master/apipage.c
+ wdt_enable(WDTO_15MS);
+ wdt_reset();
+ asm volatile (
+ "cli \n\t"
+ "ldi r29 , %[ramendhi] \n\t"
+ "ldi r28 , %[ramendlo] \n\t"
+ #if (FLASHEND>131071)
+ "ldi r18 , %[bootaddrhi] \n\t"
+ "st Y+, r18 \n\t"
+ #endif
+ "ldi r18 , %[bootaddrme] \n\t"
+ "st Y+, r18 \n\t"
+ "ldi r18 , %[bootaddrlo] \n\t"
+ "st Y+, r18 \n\t"
+ "out %[mcucsrio], __zero_reg__ \n\t"
+ "bootloader_startup_loop%=: \n\t"
+ "rjmp bootloader_startup_loop%= \n\t"
+ :
+ : [mcucsrio] "I" (_SFR_IO_ADDR(MCUCSR)),
+ #if (FLASHEND>131071)
+ [ramendhi] "M" (((RAMEND - 2) >> 8) & 0xff),
+ [ramendlo] "M" (((RAMEND - 2) >> 0) & 0xff),
+ [bootaddrhi] "M" ((((FLASH_SIZE - BOOTLOADER_SIZE) >> 1) >>16) & 0xff),
+ #else
+ [ramendhi] "M" (((RAMEND - 1) >> 8) & 0xff),
+ [ramendlo] "M" (((RAMEND - 1) >> 0) & 0xff),
+ #endif
+ [bootaddrme] "M" ((((FLASH_SIZE - BOOTLOADER_SIZE) >> 1) >> 8) & 0xff),
+ [bootaddrlo] "M" ((((FLASH_SIZE - BOOTLOADER_SIZE) >> 1) >> 0) & 0xff)
+ );
+