I Have a custom board based on APPRO DM8127 IPNC.
The board has the following configuration:
-
There are 4 RAM components, 512 MB (4Gb) each
-
Each EMIF connected to two RAM COMPONENTS through 16 bit each.
-
RAM components used are K4B4G1646B from Samsung.
- I would like to configure the board to work with 2Gbyte memory
The DDR3 support 1KB page size but need the [A0-A15] which we do not have since emif support only [A0-A14] .
The DDR3 support 2KB page size but with 10 bits[A0 to A9] Column address which EMIF seems not support.
in the spru I saw that page size configured at the SDRCR has the following limitation
FROM DM8148 reference manual:
Page Size Selection. Defines the page size of each page of the external DDR2/DDR3
memory
0 256 word page requiring 8 column address bits
1h 512 word page requiring 9 column address bits
2h 1024 word page requiring 10 column address bits
3h 2048 word page requiring 11 column address bits
FROM DDR Datasheet:
256Mb x 16
# of Bank 8
Bank Address BA0 - BA2
Auto precharge A 10 /AP A
Row Address A 0 - A 14
Column Address A 0 - A 9
BC switch on the fly A 12 /BC
Page size 2 KB
I am not sure if I have a hardware design problem, or if I am misunderstanding the limitation.
is there a way to configure the following design ?
please Advice.
Thanks
Tzvi
