MC68EC000 Motorola, MC68EC000 Datasheet - Page 44

• Manufacturer Part Number: MC68EC000
• Description: Core Processor (SCM 68000)
• Manufacturer: Motorola

MOTOROLA
1) SET RWB AND ERWB TO READ
2) PLACE FUNCTION CODE ON FC2–FC0
3) PLACE ADDRESS ON A31–A0
4) ASSERT ADDRESS STROBE (ASB)
5) ASSERT LOWER DATA STROBE (LDSB)
1) LATCH DATA
2) NEGATE LDSB AND DSB
3) NEGATE ASB
1) SET RWB AND ERWB TO READ
2) PLACE FUNCTION CODE ON FC2–FC0
3) PLACE ADDRESS ON A31-A0
4) ASSERT ADDRESS STROBE (ASB)
5) ASSERT UPPER DATA STROBE (UDSB)
1) LATCH DATA
2) NEGATE UDSB, LDSB, AND DSB
3) NEGATE ASB
AND DATA STROBE (DSB)
OR LOWER DATA STROBE (LDSB)
(BASED ON A0), AND DATA STROBE
(DSB)
ADDRESS THE DEVICE
ADDRESS THE DEVICE
ACQUIRE THE DATA
ACQUIRE THE DATA
START NEXT CYCLE
START NEXT CYCLE
Figure 3-3. Byte Read Cycle Flowchart for 16-Bit Mode
Figure 3-2. Byte Read Cycle Flowchart for 8-Bit Mode
BUS MASTER
BUS MASTER
Freescale Semiconductor, Inc.
EC000 CORE PROCESSOR USER’S MANUAL
For More Information On This Product,
Go to: www.freescale.com
1) DECODE ADDRESS
2) PLACE DATA ON D7–D0
3) ASSERT DATA TRANSFER
1) REMOVE DATA FROM D7–D0
2) NEGATE DTACKB
1) DECODE ADDRESS
2) PLACE DATA ON D7–D0 OR D15–D8
3) ASSERT DATA TRANSFER
1) REMOVE DATA FROM D7–D0
2) NEGATE DTACKB
ACKNOWLEDGE (DTACKB)
(BASED ON UDSB OR LDSB)
ACKNOWLEDGE (DTACKB)
OR D15–D8
TERMINATE THE CYCLE
TERMINATE THE CYCLE
OUTPUT THE DATA
OUTPUT THE DATA
SLAVE
SLAVE
Bus Operation
3-3