Mobile DDR-RAM (CM-i.MX27)

The core module contains 128MiB mobile DDR SDRAM.

Test in Redboot

We load a 60MB random file (generated on the PC) into the RAM two times and compare it. You need an established Ethernet connection.

RedBoot> load -r -b 0x100000 60MBrandomfile
Using default protocol (TFTP)
Raw file loaded 0x00100000-0x03cfffff, assumed entry at 0x00100000
RedBoot> load -r -b 0x3d00000 60MBrandomfile
Using default protocol (TFTP)
Raw file loaded 0x03d00000-0x078fffff, assumed entry at 0x03d00000
RedBoot> mcmp -s 0x100000 -d 0x3d00000 -l 0x3c00000   
RedBoot> 

Test in Linux

• Look into /proc/meminfo for information about memory:

root@btmxc27:~# cat /proc/meminfo 
MemTotal:       126244 kB
MemFree:        116624 kB
Buffers:             0 kB
Cached:           2360 kB
SwapCached:          0 kB
Active:           2360 kB
Inactive:         1240 kB
SwapTotal:           0 kB
SwapFree:            0 kB
Dirty:               0 kB
Writeback:           0 kB
AnonPages:        1268 kB
Mapped:            848 kB
Slab:             4200 kB
SReclaimable:     1432 kB
SUnreclaim:       2768 kB
PageTables:        164 kB
NFS_Unstable:        0 kB
Bounce:              0 kB
CommitLimit:     63120 kB
Committed_AS:     4384 kB
VmallocTotal:   122880 kB
VmallocUsed:     33188 kB
VmallocChunk:    81916 kB
root@btmxc27:~#

• The Linux memtester application provides a good SDRAM test suite.