NVMC nrf51822

[Jose Xavier]

Hi,

I just noticed that the nrf51822 doesn't have an eeprom and I already had the pcbs done. Can I use the NVMC to write USER data on the CODE (is it flash memory are?) or should I only use 32 registers provided on UICR?

[Jose Xavier]

Can you confirm me that the data wrote on these registers are only available after a reset?

[Susheel Nuguru]

not really, they are available after when you finished writing to them.

[Jose Xavier]

Datasheet says the following: 6.1.2 Writing to User Information Configuration Registers UICR registers are written as ordinary non-volatile memory. After the UICR has been written, the new UICR configuration will only take effect after a reset.

[RK]

The configuration will only take effect after a reset, which means if you write one of the UICR registers which affects configuration, like XTALFREQ, CLENR0, that change will only take effect after a reset. The values written however are available for reading after the write has completed, like other non-volatile memory.

And it is indeed 32 x 32bit words, not much, and remember you can only change bits from '1' to '0' before you have to clear the whole area.

And of course you can write to flash if you prefer, that works too.