Figure 11-47 – Freescale Semiconductor MPC8260 User Manual

Page 475

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Memory Controller

MPC8260 PowerQUICC II Family Reference Manual, Rev. 2

Freescale Semiconductor

11-57

Figure 11-47. GPCM Relaxed-Timing Write (ACS = 1x, SCY = 0, CSNT = 0,TRLX = 1)

When TRLX and CSNT are set in a write-memory access, the strobe lines, WE[0–7] are negated one clock
earlier than in the normal case. If ACS

≠ 0, CS is also negated one clock earlier, as shown in

Figure 11-48

and

Figure 11-49

. When a bank is selected to operate with external transfer acknowledge (SETA and

TRLX = 1), the memory controller does not support external devices that provide PSDVAL to complete
the transfer with zero wait states. The minimum access duration in this case is three clock cycles.

Figure 11-48. GPCM Relaxed-Timing Write (ACS = 10, SCY = 0, CSNT = 1, TRLX = 1)

Clock

Address

PSDVAL

CS

BCTL

x

WE

OE

Data

ACS = 10

ACS = 11

Clock

Address

PSDVAL

CS

BCTL

x

WE

OE

Data

ACS = 10

CSNT = 1

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