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SDRAM Controller (SDRAMC)
21-10
Freescale Semiconductor
21.4.1
SDRAM Mode/Extended Mode Register (SDMR)
The SDMR (
) writes to the mode and extended mode registers physically residing within the
SDRAM chips. These registers must be programmed during SDRAM initialization. See
“Initialization/Application Information
” for more information on the initialization sequence.
Table 21-4. SDRAMC Memory Map
Address
Register
Width
(bits)
Access
Reset Value
Section/Page
0xFC0B_8000 SDRAM Mode/Extended Mode Register (SDMR)
32
R/W
0x0000_0000
0xFC0B_8004 SDRAM Control Register (SDCR)
32
R/W
0x0000_0200
0xFC0B_8008 SDRAM Configuration Register 1 (SDCFG1)
32
R/W
0x0000_0000
0xFC0B_800C SDRAM Configuration Register 2 (SDCFG2)
32
R/W
0x0000_0000
0xFC0B_8110 SDRAM Chip Select 0 Configuration (SDCS0)
32
R/W
0x0000_0000
0xFC0B_8114 SDRAM Chip Select 1 Configuration (SDCS1)
32
R/W
0x0000_0000
Address: 0xFC0B_8000 (SDMR)
Access: SDCR[MODE_EN] = 0 User read-only
SDCR[MODE_EN] = 1 User read/write
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17
16
15 14 13 12 11 10
9
8
7
6
5
4
3
2
1
0
R
BK
AD
0
0
0 0
DDR2_AD
W
CMD
Reset 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Figure 21-4. SDRAM-Mode/Extended-Mode Register (SDMR)
Table 21-5. SDMR Field Descriptions
Field
Description
31–30
BK
Bank address. Driven onto SD_BA[1:0] along with a
LMR
/
LEMR
command. All SDRAM chip selects are asserted
simultaneously. SDCR[CKE] must be set before attempting to generate an
LMR
/
LEMR
command. The SD_BA[1:0]
value is used to select between
LMR
and
LEMR
commands.
00 Load mode register command (
LMR
)
01 Load extended mode register command (
LEMR
) for non-mobile DDR devices
10 Load extended mode register command (
LEMR
) for mobile DDR devices
11 Reserved
29–18
AD
Address. Driven onto SD_A[11:0] along with an
LMR
/
LEMR
command. The AD value is stored as the mode (or
extended mode) register data.
17
Reserved, must be cleared.
16
CMD
Command. This bit is write-only and always returns a 0 when read.
1 Generate an
LMR
/
LEMR
command
0 Do not generate any command
15–14
Reserved, must be cleared.
13–0
DDR2_AD
Address for DDR2 SDRAMs. Driven onto SD_A[13:0] along with an
LMR
/
LEMR
command. The AD value is stored as
the mode (or extended mode) register data.
Note:
SDCR[DDR_MODE, DDR2_MODE] must be set for this value to appear on the bus.
Summary of Contents for MCF54455
Page 33: ...xxviii Freescale Semiconductor ...
Page 67: ...Freescale Semiconductor 1 ...
Page 125: ...Freescale Semiconductor 1 ...
Page 145: ...Enhanced Multiply Accumulate Unit EMAC 5 21 Freescale Semiconductor ...
Page 173: ...Cache 6 28 Freescale Semiconductor ...
Page 179: ...Static RAM SRAM 7 6 Freescale Semiconductor ...
Page 207: ...Power Management 9 16 Freescale Semiconductor ...
Page 323: ...Reset Controller Module 13 8 Freescale Semiconductor ...
Page 389: ...Pin Multiplexing and Control 16 44 Freescale Semiconductor ...
Page 575: ...PCI Bus Controller 22 58 Freescale Semiconductor ...
Page 600: ...Advanced Technology Attachment ATA Freescale Semiconductor 23 25 ...
Page 601: ...Freescale Semiconductor 1 ...
Page 842: ...I2 C Interface Freescale Semiconductor 33 16 ...
Page 843: ...Freescale Semiconductor 1 ...
Page 921: ...Revision History A 6 Freescale Semiconductor ...