what is the data mask in DDR SDRAM.Actually to my knowledge what i read is it mask the byte depending on the given value.I want to know
1.what is need for masking the byte when we have to write into the memory.?
2.which byte it will mask by giving values 1 or 2?
Data Mask pin as name suggests masks the data from getting writen into the memory.
Suppose you want to mask 3rd bit in 8 bit system. Then you will set mask pins
00000100 (left most LSB). So, your information at 3rd bit is not distrubed during writing. This masked bit can be some sort of flag which is set by some previous operation which user do not want to change during next write operation into the memory.