Hi Dylan and Oleg, Thanks for the feedback! Sorry I meant kilobyte indeed, but always write it wrong, both the k-s (should be K I see now) and b-s ;)
Regarding implementation: To make it interrupt driven I guess it would be quite more a radical change, so I would look at least for now for a blocking one, which basically makes it just an additional flash area no different than the main one. About doing it similar to eeprom what I see, API wise, is that the eeprom one you link (and eeprom in general) is not page based, while the flash one (and also the RWWEE since the interface is the same) is page based. So you need always to work with pages (erase especially). So I would see it more indeed like the flashpage itself indeed. That's why my doubts on having it separate or not, since mostly what changes in the code would be the start offset, various limits now #defines (such as FLASHPAGE_NUMOF) and some flags when accessing the CPU (ie using NVMCTRL_CTRLA_CMD_RWWEEER instead of NVMCTRL_CTRLA_CMD_ER) Cheers, Federico Il giorno ven 25 gen 2019 alle ore 09:21 Dylan Laduranty <dylanladura...@gmail.com> ha scritto: > > Hello Federico, > > IIRC, this flash can be use as a virtual EEPROM. Maybe It would be better to > write a eeprom driver (like STM32 [1]) rather than add it to the flashpage > driver ? > I also think this memory is 8KB for SAML21J18 (not 8Kb), which is a lot :) > > As a side note: SAML21 also have 8KB of Low Power SRAM in addition to its 32 > KB of SRAM > > I've never played with these additional memories but I'll be happy to help. > > Cheers, > Dylan > > [1] > https://github.com/RIOT-OS/RIOT/blob/master/cpu/stm32_common/periph/eeprom.c > > Le mer. 23 janv. 2019 à 14:27, Federico Pellegrin <f...@evolware.org> a écrit > : >> >> Hi, >> Working on SAML21 based project it came to my attention also the >> presence of an 8Kb additional flash that is called "Read-While-Write" >> (or RWWEE in the datasheet) that, as far as I understood, can be >> programmed and read in a very similar way to the normal flash. This is >> currently not supported anyhow in RIOT as far as I see. This is also >> present in other SAM chips (a grep on the RIOT sam0 common includes >> tells me saml21, samd21 and samr30). >> >> Well it's just 8Kb (in saml21 case) but a customer is asking about it ;) >> >> Before starting to fiddle with code I was wondering if any of you >> already saw this or had intention to work on or had problems with this >> or.... any information would be great :) >> >> On the other side I would also be interested in an opinion if the >> access to this facility should eventually be kept totally separate >> from the current (with some possible code redundancy, but with the >> possibility no to include it into a project) or could be integrated >> into the current flashpage driver (bringing some complication of the >> logic of the current code) >> >> Thanks! >> >> Cheers, >> Federico >> _______________________________________________ >> devel mailing list >> devel@riot-os.org >> https://lists.riot-os.org/mailman/listinfo/devel > > > > -- > Dylan Laduranty > _______________________________________________ > devel mailing list > devel@riot-os.org > https://lists.riot-os.org/mailman/listinfo/devel _______________________________________________ devel mailing list devel@riot-os.org https://lists.riot-os.org/mailman/listinfo/devel
