int __attribute__((noreturn)) main(void) {
uint16_t idlePolls = 0;
/* initialize */
wdt_disable(); /* main app may have enabled watchdog */
tiny85FlashInit();
bootLoaderInit();
if (bootLoaderCondition()) {
initForUsbConnectivity();
do {
usbPoll();
_delay_us(100);
idlePolls++;
if (events) idlePolls = 0;
// these next two freeze the chip for ~ 4.5ms, breaking usb protocol
// and usually both of these will activate in the same loop, so host
// needs to wait > 9ms before next usb request
if (isEvent(EVENT_ERASE_APPLICATION)) eraseApplication();
if (isEvent(EVENT_WRITE_PAGE)) tiny85FlashWrites();
if (isEvent(EVENT_FINISH)) { // || AUTO_EXIT_CONDITION()) {
tiny85FinishWriting();
# if BOOTLOADER_CAN_EXIT
_delay_ms(10); // removing delay causes USB errors
break;
# endif
}
// # if BOOTLOADER_CAN_EXIT
// // exit if requested by the programming app, or if we timeout waiting for the pc with a valid app
// if (isEvent(EVENT_EXIT_BOOTLOADER) || AUTO_EXIT_CONDITION()) {
// //_delay_ms(10);
// break;
// }
// # endif
clearEvents();
} while(bootLoaderCondition()); /* main event loop */
}
leaveBootloader();
}
static inline void tiny85FlashInit(void)
{
// check for erased first page (no bootloader interrupt vectors), add vectors if missing
if(pgm_read_word(RESET_VECTOR_OFFSET * 2) != 0xC000 + (BOOTLOADER_ADDRESS/2) - 1 ||
pgm_read_word(USBPLUS_VECTOR_OFFSET * 2) != 0xC000 + (BOOTLOADER_ADDRESS/2) - 1)
{
// TODO: actually need to erase here? how could we end up with missing vectors but application data higher up?
# if HAVE_CHIP_ERASE
eraseApplication();
# else
fillFlashWithVectors();
# endif
}
// TODO: necessary to reset CURRENT_ADDRESS?
CURRENT_ADDRESS = 0;
# ifdef APPCHECKSUM
checksum = 0;
# endif
}
static inline void tiny85FlashWrites(void)
{
#if HAVE_CHIP_ERASE
if(eraseRequested)
{
_delay_ms(2);
cli();
eraseApplication();
sei();
#ifdef APPCHECKSUM
checksum = 0;
#endif
eraseRequested = 0;
}
#endif
if(flashPageLoaded)
{
_delay_ms(2);
// write page to flash, interrupts will be disabled for several milliseconds
cli();
if(CURRENT_ADDRESS % SPM_PAGESIZE)
fillFlashWithVectors();
else
writeFlashPage();
sei();
flashPageLoaded = 0;
if(isLastPage)
{
// store number of bytes written so rest of flash can be filled later
writeSize = CURRENT_ADDRESS;
appWriteComplete = 1;
}
}
}
int main(void) {
/* initialize */
#ifdef RESTORE_OSCCAL
uint8_t osccal_default = OSCCAL;
#endif
#if (!SET_CLOCK_PRESCALER) && LOW_POWER_MODE
uint8_t prescaler_default = CLKPR;
#endif
wdt_disable(); /* main app may have enabled watchdog */
tiny85FlashInit();
bootLoaderInit();
if (bootLoaderStartCondition()) {
#if LOW_POWER_MODE
// turn off clock prescalling - chip must run at full speed for usb
// if you might run chip at lower voltages, detect that in bootLoaderStartCondition
CLKPR = 1 << CLKPCE;
CLKPR = 0;
#endif
initForUsbConnectivity();
do {
usbPoll();
_delay_us(100);
idlePolls++;
// these next two freeze the chip for ~ 4.5ms, breaking usb protocol
// and usually both of these will activate in the same loop, so host
// needs to wait > 9ms before next usb request
if (isEvent(EVENT_ERASE_APPLICATION)) eraseApplication();
if (isEvent(EVENT_WRITE_PAGE)) tiny85FlashWrites();
# if BOOTLOADER_CAN_EXIT
if (isEvent(EVENT_EXECUTE)) { // when host requests device run uploaded program
break;
}
# endif
clearEvents();
} while(bootLoaderCondition()); /* main event loop runs so long as bootLoaderCondition remains truthy */
}
// set clock prescaler to desired clock speed (changing from clkdiv8, or no division, depending on fuses)
#if LOW_POWER_MODE
#ifdef SET_CLOCK_PRESCALER
CLKPR = 1 << CLKPCE;
CLKPR = SET_CLOCK_PRESCALER;
#else
CLKPR = 1 << CLKPCE;
CLKPR = prescaler_default;
#endif
#endif
// slowly bring down OSCCAL to it's original value before launching in to user program
#ifdef RESTORE_OSCCAL
while (OSCCAL > osccal_default) { OSCCAL -= 1; }
#endif
leaveBootloader();
}
