clock cycles needed for eeprom write

[prudhvichitturi]

Hello , 

i am looking to know for STM32L051 how long will it take a byte to be written in to eeprom.

while writing eeprom does it have any limitations like UART intteruptions?

[TDK]

If it's the same as the STM32L1 family (which it probably is), it will not stall the bus unless you read/write to the same bank before the first operation is done.

Datasheet says programming time is 3.94 ms max.

[Piranha]

Ironically that time is about 10 to 100 times worse than for a software EEPROM emulation or a proper storage system in FLASH memory.

[prudhvichitturi]

The below is the function i use , 

 flash_unlock( );
memcpy( &data_w, data_ptr, sizeof( data_w ) );
status = HAL_FLASHEx_DATAEEPROM_Program( TYPEPROGRAMDATA_WORD, Address_Src, INVERTED_DATA( data_w ) );
flash_lock( );

[prudhvichitturi]

from the above , does it take longer than 3.94?

[Tesla DeLorean · Accepted solution]

Use a TIM counting off micro-seconds to measure the time across the functions. Or toggle a GPIO and scope it

[TDK]

It shouldn't. Measure it, shouldn't stall at all. Not sure if you can lock the flash when a write is in progress.