// Private method
uint8_t EEPROM_24XX1025::writeChunk(uint32_t fulladdr, const void *data, uint8_t bytesToWrite) {
// Used to turn 1-128 byte writes into full page writes (i.e. turn them into proper single-page writes)
if (bytesToWrite == 0 || bytesToWrite > 128 || fulladdr >= DEVICE_SIZE)
return 0;
if (fulladdr + bytesToWrite > DEVICE_SIZE)
bytesToWrite = DEVICE_SIZE - fulladdr;
// Calculate the 16-bit address, and the page number of the first and second (if applicable)
// blocks we're going to write to.
uint32_t pageaddr = TO_PAGEADDR(fulladdr);
uint8_t firstBlock = BLOCKNUM(fulladdr);
uint8_t secondBlock = BLOCKNUM(fulladdr + bytesToWrite - 1);
// These page numbers are *relative to the block number*, i.e. firstPage = 0 may mean at byte 0 or byte 65536
// depending on firstBlock above. Same goes for secondPage/secondBlock of course.
uint16_t firstPage = pageaddr / 128; // pageaddr is already relative to block!
uint16_t secondPage = (TO_PAGEADDR(pageaddr + bytesToWrite - 1))/128;
if (firstPage == secondPage && firstBlock == secondBlock) {
// Data doesn't "cross the border" between pages. Easy!
return writeSinglePage(fulladdr, data, bytesToWrite);
}
else {
// The data spans two pages, e.g. begins at address 120 and is 12 bytes long, which would make it go
// past the edge of this page (addresses 0 - 127) and onto the next.
// We need to split this write manually.
uint8_t bytesInFirstPage = ((firstPage + 1) * 128) - pageaddr;
uint8_t bytesInSecondPage = bytesToWrite - bytesInFirstPage;
uint8_t ret = 0;
// Write the data that belongs to the first page
if ((ret = writeSinglePage(TO_FULLADDR(firstBlock, pageaddr), data, bytesInFirstPage))
!= bytesInFirstPage)
{
return ret;
}
// Write the data that belongs to the second page
if ((ret = writeSinglePage(TO_FULLADDR(secondBlock, secondPage * 128), (const void*)((byte *)data + bytesInFirstPage), bytesInSecondPage))
!= bytesInSecondPage)
{
return bytesInFirstPage + ret;
}
}
return bytesToWrite;
}
int main(int argc, char *argv[])
{
HEX_LINE *hexFile;
initializeHardware();
deactivateReset();
enableAVRProgramming();
hexFile = parseHexFile(argv[1]);
printHexfile(hexFile);
eraseAVRFlash();
writeSinglePage(hexFile);
readSinglePage();
deactivateReset();
deleteHexfile(hexFile);
freeHardwareResources();
return 0;
} // end main()
