Open Rex - DDR3 Memory Address

[justaelvis]

Hi Robert,
I wonder why open rex use all 16 address lines for DDR3 interface, cause as I read in Micron 4Gb DDR3 Addressing it said for 256Mx16 row addressing is A[14:0] and column addressing is A[9:0].
And why the termination resistor of address, command and control is 47 ohm.
Thank you!

[robertferanec]

I wonder why open rex use all 16 address lines for DDR3 interface, cause as I read in Micron 4Gb DDR3 Addressing it said for 256Mx16 row addressing is A[14:0] and column addressing is A[9:0].

- It is there to support 8Gb memory chips: http://www.voipac.com/#iMX6-SBC-532441111

And why the termination resistor of address, command and control is 47 ohm.

- this was taken from reference schematic