Synchronous DRAM (60x Bus)
MSC711x Application Development System (MSC711xADS) Reference Manual, Rev. 1
Freescale Semiconductor
47
Figure 5-9. 60x SDRAM Connection Scheme
5.8.1
SDRAM Programming
After power-up, software must initialize the SDRAM to establish its mode of operation, as follows:
1.
Issue the
P
RECHARGE
-A
LL
command.
2.
Issue eight
CBR
R
EFRESH
commands.
3.
Issue the
M
ODE
-S
ET
command.
During the
M
ODE
-S
ET
command, data is passed to the mode register through the SDRAM address lines.
The MPC8272 SDRAM machine fully supports this command.
Before the SDRAM can be programmed, the MPC8272 SDRAM machine must be initialized. Table 5-3 shows the
Mode Register programming values. These show the register lines on the SDRAM device (
A[11–0]
) and the
meaning of each line.
S]
Table 5-3. DRAM Mode Register Programming
MPC8272 Mode
Register Line
SDRAM
Address Linea
SDRAM Mode
Register Field
Value
Description
A17
A11 (MSB)
Reserved
0
MT48LC8M16A2-6
CS0
RAS
CAS
WE
BA
A11
A10
A9
A[8–0]
DQMB[0–7]
DQ[0–63]
CKE
CLK
CS2
SDRAS
SDCAS
SDWE
BANKSEL[1–2]
A17
SDA10
A19
A[20–28]
SDDQM[0–7]
D[0–63]
SYSCLK