Command and ap during – Motorola MPC8260 User Manual
Page 325
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MOTOROLA
Chapter 10. Memory Controller
10-49
Part III. The Hardware Interface
Now, from the SDRAM device point of view, during an
ACTIVATE
command, its address
port should look like Table 10-22
Table 10-19 indicates that to multiplex A[6Ð17] over A[17Ð28], PSDMR[SDAM] must be
011 and, because the internal bank selects are multiplexed over A[15Ð16], PSDMR[BSMA]
must be 010 (only the lower two bank select lines are used).
Note that if the device is connected to the BNKSEL pins, the value of PSDMR[BSMA] has
no effect. In the above example, address lines [18Ð19] are output on BNKSEL1 and
BNKSEL0, accordingly.
During a
READ
/
WRITE
command, the address port should look like Table 10-23.
Because AP alternates with A[7] of the row lines, set PSDMR[SDA10] = 011. This outputs
A[7] on the SDA10 line during the
ACTIVATE
command and AP during
READ
/
WRITE
and
CBR commands.
Table 10-24 shows the register conÞguration. Not shown are PSRT and MPTPR, which
should be programmed according to the device refresh requirements:
Table 10-22. SDRAM Device Address Port during
ACTIVATE
Command
ТA[0Р14]У
A[15Ð16]
A[17Ð28]
A[29Р31]
С
Internal bank select (A[18Ð19])
Row (A[6Ð17])
n.c.
Table 10-23. SDRAM Device Address Port during
READ
/
WRITE
Command
ТA[0Р14]У
A[15Ð16]
A[17]
A[18]
A[19]
A[20Ð28]
A[29Р31]
С
Internal bank select
DonÕt care
AP
DonÕt care
Column
n.c.
Table 10-24. Register Settings (Page-Based Interleaving
Register
Settings
BRx
BA
Base address
PS
00 = 64-bit port size
DECC
00
WP
0
MS
010 = SDRAM-60x bus
EMEMC
0
ATOM
00
DR
0
V
1
ORx
AM
1111_1100_0000
LSDAM
00000
BPD
01
ROWST
0110
NUMR
011
PMSEL
0
IBID
0
PSDMR
PBI
1
RFEN
1
OP
000
SDAM
011
BSMA
010
SDA10
011
RFRC
from device data sheet
PRETOACT
from device data sheet
ACTTOROW
from device data sheet
BL
0
LDOTOPRE
from device data sheet
WRC
from device data sheet
EAMUX
0
BUFCMD
0
CL
from device data sheet