Freescale Semiconductor MPC8260 - Manual (Page 456)

Memory Controller
MPC8260 PowerQUICC II Family Reference Manual, Rev. 2
11-38 Freescale Semiconductor
Note that in 60x-compatible mode, the 60x address must be latched and multiplexed by glue logic that is
controlled by ALE and SDAMUX, however, the user still has to configure PSDMR[SDAM].
On the local bus, only the lower 18 bits of the address are output. Table 11-20 shows SDRAM address
multiplexing for A0–A15.
Table 11-21 shows SDRAM address multiplexing for A16–A31.
11.4.6 SDRAM Device-Specific Parameters
The software is responsible for setting correct values to some device-specific parameter that can be
extracted from the data sheet. The values are stored in the ORx and P/LSDMR registers. These parameters
include the following:
• Precharge to activate interval (P/LSDMR[PRETOACT]). See Section 11.4.6.1,
“Precharge-to-Activate Interval.”
• Activate to read/write interval (P/LSDMR[ACTTORW]). See Section 11.4.6.2, “Activate to
Read/Write Interval.”
• CAS latency, column address to first data out (P/LSDMR[CL]). See Section 11.4.6.3, “Column
Address to First Data Out—CAS Latency.”
Table 11-20. SDRAM Address Multiplexing (A0–A15)
SDAM
External Bus
Address
Pins
A0 A1 A2 A3 A4 A5 A6 A7 A8 A9 A10 A11 A12 A13 A14 A15
000
Signal
driven on
external pins
when
address
multiplexing
is enabled
— — — — — — — — — — — — — A5 A6 A7
001 — — — — — — — — — — — — — — A5 A6
010 — — — — — — — — — — — — — — — A5
011 — — — — — — — — — — — — — — — —
100 — — — — — — — — — — — — — — — —
101 — — — — — — — — — — — — — — — —
Table 11-21. SDRAM Address Multiplexing (A16–A31)
SDAM
External Bus
Address
Pins
A16 A17 A18 A19 A20 A21 A22 A23 A24 A25 A26 A27 A28 A29 A30 A31
000
Signal
driven on
external pins
when
address
multiplexing
is enabled
A8 A9 A10 A11 A12 A13 A14 A15 A16 A17 A18 A19 A20 A21 A22 A23
001 A7 A8 A9 A10 A11 A12 A13 A14 A15 A16 A17 A18 A19 A20 A21 A22
010 A6 A7 A8 A9 A10 A11 A12 A13 A14 A15 A16 A17 A18 A19 A20 A21
011 A5 A6 A7 A8 A9 A10 A11 A12 A13 A14 A15 A16 A17 A18 A19 A20
100 A4 A5 A6 A7 A8 A9 A10 A11 A12 A13 A14 A15 A16 A17 A18 A19
101 — — A5 A6 A7 A8 A9 A10 A11 A12 A13 A14 A15 A16 A17 A18