Main memory flash MSP430G2553

Simple math: one segment covers all memory with the same upper address bits while the lower 9 bits (for 512 bytes) are don’t care.

But why do you need 8 bytes for time? In seconds, this would be 6^11 years. In microseconds (1MHz resolution) this still would be ~600.000 years. Does your timestamp cover the full range from the big bang to the end of the universe?

TeraTerm doesn’t read the MSP memory directly. So you can convert the 4-byte timestamp when reading it from memory and sending it to TeraTerm. No need to store more data than required. After all, you’re filling more than one sector per hour, so your memory will overflow soon. Saving space will likely become vital when the project matures from a lab proof of concept to a real device.

Yes don't waste Flash, my program uses 3bytes to store 2bit data plus time.
I only use 2bits for year,as I can tell that the year can not be in the future and 4 years of data is enough.
Sure unix time of seconds from 1970 probably would be easier and maybe use less

byte 1 : xx_yy_mmmm
byte 2 : ddddd_hhh
byte 3 : hh_mmmmmm

TimetStamp Structure (a 24bit value MSB listed first)
______________________________________________________

Bits 23 and 22 for  data

Year   bits 21 and 20
2 bits  0-99 ( &11b  0-3  possible )

Month bits 19 to 16
4 bits  1-12 ( 0-16 possible )

Day bits 15-11
5 bits 1-31 ( 0-31 possible )

Hour bits 10-6
5 bits 0-23 ( 0-31 possible )

Minute bits 5-0
6 bits 0-59 ( 0-63 possible )