| ??? 08/16/07 11:22 Read: times |
#143332 - code sketch Responding to: ???'s previous message |
For a start I'd try something like this now:
The sum starts with something non-zero to avoid all zero data bytes and all I do is adding the data to this. WORD sum; BYTE chksum; sum=0x3c45; for(i=EEPROM_MONITOR;i<EEPROM_CHECKSUM;i++) sum += EEPROM_read(i); chksum = 0xff-((BYTE)(sum & 0xff00) >> 8); It reminds me a bit of the XMODEM checksumming scheme as i think of it. I mainly need a YES/NO answer for the checksum to keep it simple. Any further ideas? cheers, Matthias |
| Topic | Author | Date |
| Simple EEPROM checksumming | 01/01/70 00:00 | |
| Pitfalls | 01/01/70 00:00 | |
| a checksum out of 2 bytes? | 01/01/70 00:00 | |
| It's an "either - or" ... | 01/01/70 00:00 | |
| code sketch | 01/01/70 00:00 | |
| a simple checksum | 01/01/70 00:00 | |
| CRC8 instead of CR32 | 01/01/70 00:00 | |
| I am talking about CRC-16 not CRC-8 | 01/01/70 00:00 | |
| oups | 01/01/70 00:00 | |
| how much data? | 01/01/70 00:00 | |
| approx 40-60 bytes | 01/01/70 00:00 | |
| I use 2 copies and a counter for that | 01/01/70 00:00 | |
| adding to Jan's post | 01/01/70 00:00 | |
| Here's one method | 01/01/70 00:00 | |
| another interesting scheme! | 01/01/70 00:00 | |
| Try the Dallas 1-wire CRC | 01/01/70 00:00 | |
| another good idea but... | 01/01/70 00:00 | |
| I just meant the CRC | 01/01/70 00:00 | |
oups | 01/01/70 00:00 |