4 sdram machine, Table 11-18. sdram interface signals, Sdram machine -33 – Freescale Semiconductor MPC8260 User Manual

Page 451: Sdram interface signals -33, N 11.3.13, N 11.3.14

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Memory Controller

MPC8260 PowerQUICC II Family Reference Manual, Rev. 2

Freescale Semiconductor

11-33

11.3.13 60x Bus Error Status and Control Registers (TESCR

x

)

These registers indicate the source of an error that caused TEA or MCP to be asserted on the 60x bus. See

Section 4.3.2.10, “60x Bus Transfer Error Status and Control Register 1 (TESCR1),”

and

Section 4.3.2.11,

“60x Bus Transfer Error Status and Control Register 2 (TESCR2).”

11.3.14 Local Bus Error Status and Control Registers (L_TESCR

x

)

These registers indicate the source of an error that causes TEA or MCP to be asserted on the local bus. See

Section 4.3.2.12, “Local Bus Transfer Error Status and Control Register 1 (L_TESCR1),”

and

Section 4.3.2.13, “Local Bus Transfer Error Status and Control Register 2 (L_TESCR2).”

11.4

SDRAM Machine

The PowerQUICC II provides one SDRAM interface (machine) for the 60x bus and one for the local bus.
The machines provide the necessary control functions and signals for JEDEC-compliant SDRAM devices.

Each bank can control a SDRAM device on the 60x or the local bus.

Table 11-18

describes the SDRAM

interface signals controlled by the memory controller.

Additional controls are available in 60x-compatible mode (60x bus only):

ALE—External address latch enable

PSDAMUX—External address multiplexing control (asserted = row, negated = column)

Throughout this section, whenever a signal is named, the reference is to the 60x or local bus signal,
according to the accessed bank’s machine-select.

Figure 11-19. shows an eight-bank, 128-Mbyte system. Each bank consists of eight 2 x 1-Mbit x 8
SDRAMs. Note that the SDRAM memory clock must operate at the same frequency as, and be
phase-aligned with, the system clock.

Table 11-18. SDRAM Interface Signals

60x Bus

Local Bus

Comments

CS[0–11]

Device select

PSDRAS

LSDRAS

RAS

SDCAS

LSDCAS

CAS

SDWE

LSDWE

WEN

SDA10

LSDA10

“A10” control

DQM[0–7]

LDQM[0–3]

Byte select

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