Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]
Groups > comp.arch.embedded > #27813
| From | pozz <pozzugno@gmail.com> |
|---|---|
| Newsgroups | comp.arch.embedded |
| Subject | Re: Serial EEPROM or Serial Flash? |
| Date | 2018-06-15 15:01 +0200 |
| Organization | A noiseless patient Spider |
| Message-ID | <pg0dc3$npv$2@dont-email.me> (permalink) |
| References | (1 earlier) <pfth8a$vpp$1@dont-email.me> <pfvqei$9t7$1@dont-email.me> <8bdfea77-13fc-462a-a01a-d7cd97e9d6c6@googlegroups.com> <pfvufp$uha$1@dont-email.me> <bee22e6a-1942-4242-887c-42dc5907d5ae@googlegroups.com> |
Il 15/06/2018 11:20, Jack ha scritto: > Il giorno venerdì 15 giugno 2018 10:47:55 UTC+2, pozz ha scritto: >> Il 15/06/2018 09:54, Jack ha scritto: >>> Il giorno venerdì 15 giugno 2018 09:39:03 UTC+2, pozz ha scritto: >>> >>>> Why do I need checksum? The only thing that comes in mind is to prevent >>>> writing errors: for example, I want to write 0x00 but the value really >>>> written is 0x01, maybe for a noise on the serial bus. >>>> >>>> To solve this situation, I need checksum... but also I need to re-read >>>> and re-calculate the checksum at *every* area writing... and start a new >>>> writing if something was wrong. >>> >>> At power up, when you read Area1 (for example) how do you know that the data are not corrupted (even if magic/counter are correct)? >> >> In my application I think I can ignore two problematic events: >> >> - the value really written is different for a noise on the bus signals; >> - the value really written is different for physical damage of the memory. > > You can ignore these events only if you don't care about the data > Else you need to find a strategy manage the errors (in general this is easy: just read back the data after you're sure that the write ended). I know it should be better... however I think they are so rare events that I could ignore in my application (that isn't so critical for humans). >> If I ignore these events/situations, I think checksums aren't needed and >> I can consider only magic/counter. > > The issue is not after write, the issue is after powerup, when you read the data from flash, you don't know if the data is correct or corrupted, even if the magic number/counter a consistent. > A checksum is a way to be sure of this (but you can't recover if something is corrupted). Another is to write the same data multiple times and then use a mojority vote to decide if they are correct or not (and recover if there is something corrupted). > > Bye Jack >
Back to comp.arch.embedded | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread
Serial EEPROM or Serial Flash? pozz <pozzugno@gmail.com> - 2018-06-14 12:20 +0200
Re: Serial EEPROM or Serial Flash? David Brown <david.brown@hesbynett.no> - 2018-06-14 12:49 +0200
Re: Serial EEPROM or Serial Flash? pozz <pozzugno@gmail.com> - 2018-06-15 09:38 +0200
Re: Serial EEPROM or Serial Flash? Jack <jack4747@gmail.com> - 2018-06-15 00:54 -0700
Re: Serial EEPROM or Serial Flash? Reinhardt Behm <rbehm@hushmail.com> - 2018-06-15 16:26 +0800
Re: Serial EEPROM or Serial Flash? Jack <jack4747@gmail.com> - 2018-06-15 01:31 -0700
Re: Serial EEPROM or Serial Flash? pozz <pozzugno@gmail.com> - 2018-06-15 10:50 +0200
Re: Serial EEPROM or Serial Flash? Reinhardt Behm <rbehm@hushmail.com> - 2018-06-15 17:03 +0800
Re: Serial EEPROM or Serial Flash? pozz <pozzugno@gmail.com> - 2018-06-15 14:59 +0200
Re: Serial EEPROM or Serial Flash? David Brown <david.brown@hesbynett.no> - 2018-06-15 15:51 +0200
Re: Serial EEPROM or Serial Flash? pozz <pozzugno@gmail.com> - 2018-06-15 10:47 +0200
Re: Serial EEPROM or Serial Flash? Jack <jack4747@gmail.com> - 2018-06-15 02:20 -0700
Re: Serial EEPROM or Serial Flash? Stef <stef33d@yahooI-N-V-A-L-I-D.com.invalid> - 2018-06-15 13:41 +0200
Re: Serial EEPROM or Serial Flash? pozz <pozzugno@gmail.com> - 2018-06-15 15:01 +0200
Re: Serial EEPROM or Serial Flash? David Brown <david.brown@hesbynett.no> - 2018-06-15 11:25 +0200
Re: Serial EEPROM or Serial Flash? pozz <pozzugno@gmail.com> - 2018-06-15 15:10 +0200
Re: Serial EEPROM or Serial Flash? Jack <jack4747@gmail.com> - 2018-06-15 06:51 -0700
Re: Serial EEPROM or Serial Flash? David Brown <david.brown@hesbynett.no> - 2018-06-15 16:21 +0200
Re: Serial EEPROM or Serial Flash? pozz <pozzugno@gmail.com> - 2018-06-15 17:20 +0200
Re: Serial EEPROM or Serial Flash? Richard Damon <Richard@Damon-Family.org> - 2018-06-15 13:11 -0400
Re: Serial EEPROM or Serial Flash? pozz <pozzugno@gmail.com> - 2018-06-15 22:54 +0200
Re: Serial EEPROM or Serial Flash? Richard Damon <Richard@Damon-Family.org> - 2018-06-15 18:25 -0400
Re: Serial EEPROM or Serial Flash? pozz <pozzugno@gmail.com> - 2018-06-16 08:26 +0200
Re: Serial EEPROM or Serial Flash? Richard Damon <Richard@Damon-Family.org> - 2018-06-16 09:20 -0400
Re: Serial EEPROM or Serial Flash? pozz <pozzugno@gmail.com> - 2018-06-16 19:38 +0200
Re: Serial EEPROM or Serial Flash? Richard Damon <Richard@Damon-Family.org> - 2018-06-16 16:41 -0400
Re: Serial EEPROM or Serial Flash? pozz <pozzugno@gmail.com> - 2018-06-16 23:05 +0200
Re: Serial EEPROM or Serial Flash? David Brown <david.brown@hesbynett.no> - 2018-06-17 18:41 +0200
Re: Serial EEPROM or Serial Flash? pozz <pozzugno@gmail.com> - 2018-06-16 20:12 +0200
Re: Serial EEPROM or Serial Flash? David Brown <david.brown@hesbynett.no> - 2018-06-17 19:27 +0200
Re: Serial EEPROM or Serial Flash? pozz <pozzugno@gmail.com> - 2018-06-19 17:40 +0200
Re: Serial EEPROM or Serial Flash? Richard Damon <Richard@Damon-Family.org> - 2018-06-17 17:05 -0400
Re: Serial EEPROM or Serial Flash? pozz <pozzugno@gmail.com> - 2018-06-19 17:44 +0200
Re: Serial EEPROM or Serial Flash? Richard Damon <Richard@Damon-Family.org> - 2018-06-19 23:14 -0400
Re: Serial EEPROM or Serial Flash? pozz <pozzugno@gmail.com> - 2018-06-20 11:03 +0200
Re: Serial EEPROM or Serial Flash? Richard Damon <Richard@Damon-Family.org> - 2018-06-20 08:03 -0400
Re: Serial EEPROM or Serial Flash? Michael Karas <mkaras@carousel-design.com> - 2018-06-23 09:43 -0700
csiph-web