RM0082
DDR memory controller (MPMC)
Doc ID 018672 Rev 1
189/844
cs_map [1:0]
Sets the mask that determines which chip select pins are active, with
each bit representing a different chip select. The user address chip
select field will be mapped into the active chip selects indicated by this
parameter in ascending order from lowest to highest. This allows the
Memory Controller to map the entire contiguous user address into any
group of chip selects. Bit 0 of this parameter corresponds to chip select
[0], bit 1 corresponds to chip select [1], etc.
The number of chip selects, i.e. the number of bits set to 1 in this
parameter, must be a power of 2.
ddrii_sdram_mode [0]
Selects between the DDR1(Mobile) and DDR2 modes of operation.
(2)
1'b0 - DDR1(mobile) mode
1'b1 - DDR2 mode
dll_bypass_mode [0]
Defines the behavior of the DLL bypass logic and establishes which set
of delay parameters will be used.
When dll_bypass_mode is set to 'b0, the values programmed in the
dll_dqs_delay_X, dqs_out_shift, and wr_dqs_shift are used. These
parameters add fractional increments of the clock to the specified lines.
When dll_bypass_mode is set to 'b1, the values programmed into the
dll_dqs_delay_bypass_X, dqs_out_shift_bypass, and
wr_dqs_shift_bypass are used. These parameters specify the actual
number of delay elements added to each of the lines. If the total delay
time programmed into the delay parameters exceeds the number of
delay elements in the delay chain, the delay will be set to the maximum
number of delay elements in the delay chain.
1'b0 - Normal operational mode.
1'b1 - Bypass the DLL master delay line.
dll_dqs_delay_X [6:0]
Sets the delay for the read_dqs signal from the DDR SDRAM devices
for dll_rd_dqs_slice X. This delay is used center the edges of the
read_dqs signal so that the READ data will be captured in the middle of
the valid window in the I/O logic.
Each increment of this parameter adds a delay of 1/128 of the system
clock. The same delay will be added to the read_dqs signal for each
byte of the READ data.
(3)
dll_dqs_delay_bypass_X
[9:0]
Sets the delay for the read_dqs signal from the DDR SDRAM devices
for dll_rd_dqs_slice X for READs when the DLL is being bypassed. This
delay is used to center the edges of the read_dqs signal so that the
READ data will be captured in the middle of the valid window in the I/O
logic.
The value programmed into this parameter sets the actual number of
delay elements in the read_dqs line. The same delay will be added to
the read_dqs signal for each byte of the READ data. If the total delay
time programmed exceeds the number of delay elements in the delay
chain, the delay will be set internally to the maximum number of delay
elements available.
(4)
dll_increment [9:0]
Defines the number of delay elements to recursively increment the
dll_start_point parameter with when searching for lock.
Table 153.
Memory controller parameters (continued)
Parameter
Description