mcf5282 Freescale Semiconductor, Inc, mcf5282 Datasheet - Page 231

• Manufacturer Part Number: mcf5282
• Manufacturer: Freescale Semiconductor, Inc

Note the following characteristics of a basic read:
States are described in
13.4.4
During a write cycle, the processor sends data to the memory or to a peripheral device. The write cycle
flowchart is shown in
Freescale Semiconductor
•
•
•
A[31:0], SIZ[1:0]
CSn, BSn, OE
In S3, data is made available by the external device on the falling edge of CLKOUT and is sampled
on the rising edge of CLKOUT with TA asserted.
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.
CLKOUT
D[31:0]
Write Cycle
1.
2.
3.
4.
5.
6.
1.
2.
1.
R/W
TIP
TS
TA
Set R/W to write
Place address on A[31:0]
Assert TIP and SIZ[1:0]
Assert TS
Place data on D[31:0]
Negate TS
Sample TA low
Stop driving data from D[31:0]
Start next cycle
ColdFire processor
Figure
Table
MCF5282 and MCF5216 ColdFire Microcontroller User’s Manual, Rev. 3
13-3.
13-7.
Figure 13-6. Basic Read Bus Cycle
Figure 13-7. Write Cycle Flowchart
S0
S1
S2
S3
Read
1.
2.
3.
1.
S4
Decode address
Store data on D[31:0]
Assert TA
Negate TA
External Device
S5
External Interface Module (EIM)
13-7