Motorola MCF5281 사용자 설명서

13-8

MOTOROLA

 

• In S4, the external device can stop driving data after the rising edge of CLKOUT. 

However data could be driven up to S5. 

• For a read cycle, the external device stops driving data between S4 and S5. 

States are described in Table 13-3. 

During a write cycle, the MCF5282 sends data to the memory or to a peripheral device. The
write cycle flowchart is shown in Figure 13-7.

The write cycle timing diagram is shown in Figure 13-8.

Table 13-3 describes the six states of a basic write cycle.

1.

Set R/W to write

2.

Place address on A[31:0]

3.

Assert TIP and SIZ[1:0] 

4.

Assert TS

5.

Place data on D[31:0]

6.

Negate TS

1.

Decode address 

2.

Store data on D[31:0]

3.

Assert TA

1.

Sample TA low 

2.

Stop driving data from D[31:0]

1.

Negate TA

1.

Start next cycle

R/W

TIP

TS

D[31:0]

TA

S0

S1

S2

S3

S4

S5

Write

CLKOUT

CSn, BSn

A[31:0], SIZ[1:0]