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Figure 21: mcf5307 memory read cycle, Figure 22: mcf5307 memory write cycle, 3 burst cycles – Epson S1D13705 User Manual

Page 485

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Epson Research and Development

Page 9

Vancouver Design Center

Interfacing to the Motorola MCF5307 "ColdFire" Microprocessor

S1D13705

Issue Date: 01/02/13

X27A-G-011-02

Figure 2-1: MCF5307 Memory Read Cycle

Figure 2-2: MCF5307 Memory Write Cycle

2.1.3 Burst Cycles

Burst cycles are very similar to normal cycles, except that they occur as a series of four
back-to-back, 32-bit memory reads or writes, with the TIP (Transfer In Progress) output
asserted continuously through the burst. Burst memory cycles are mainly intended to facil-
itate cache line fill from program or data memory; they are typically not used for transfers
to or from IO peripheral devices such as the S1D13705. The MCF5307 chip selects provide
a mechanism to disable burst accesses for peripheral devices which are not able to support
them.

A[31:0]

D[31:0]

SIZ[1:0], TT[1:0]

TS

TA

BCLK0

Wait States

Transfer Start

Transfer

Next Transfer

Sampled when TA low

R/W

Complete

Starts

TIP

A[31:0]

D[31:0]

SIZ[1:0], TT[1:0]

TS

TA

BCLK0

Wait States

Transfer Start

R/W

Valid

Transfer

Next Transfer

Complete

Starts

TIP