MC68EC040RC20A Freescale Semiconductor, MC68EC040RC20A Datasheet - Page 174

• Manufacturer Part Number: MC68EC040RC20A
• Description: IC MPU 32BIT 20MHZ 179-PGA
• Manufacturer: Freescale Semiconductor

Specifications of MC68EC040RC20A

• Processor Type: M680x0 32-Bit
• Speed: 20MHz
• Voltage: 5V
• Mounting Type: Surface Mount
• Package / Case: 179-PGA
• Lead Free Status / RoHS Status: Contains lead / RoHS Compliant
• Features: -

The interrupt acknowledge bus cycle is a read transfer. It differs from a normal read cycle
in the following respects:
The responding device places the vector number on the data bus during the interrupt
acknowledge bus cycle, and the cycle is terminated normally with TA. Figures 7-21 and
7-22 illustrate a flowchart and functional timing diagram for an interrupt acknowledge cycle
terminated with TA.
7-32
1. TT1 and TT0 = $3 to indicate an acknowledged bus cycle.
2. Address signals A31–A0 are set to all ones ($FFFFFFFF).
3. TM2–TM0 are set to the interrupt request level (the inverted values of IPL2–IPL0).
10) ASSERT TIP
1) IPEND RECOGNIZED, WAIT FOR
2) SET R/W TO READ
3) DRIVE A31–A0 TO $FFFFFFFF
4) DRIVE UPA1, UPA0 TO $0
5) SET SIZE TO BYTE
6) SET TRANSFER TYPE ON TT1, TT0 TO $3
7) PLACE INTERRUPT LEVEL ON TM2–TM0
8) NEGATE CIOUT
9) ASSERT TS FOR ONE CLOCK
1) LATCH VECTOR NUMBER
INSTRUCTION BOUNDARY
Figure 7-21. Interrupt Acknowledge Bus Cycle Flowchart
ACKNOWLEDGE INTERRUPT
START NEXT CYCLE
ACQUIRE DATA
PROCESSOR
Freescale Semiconductor, Inc.
For More Information On This Product,
M68040 USER’S MANUAL
Go to: www.freescale.com
1) PLACE VECTOR NUMBER ON BYTE D7–D0
2) ASSERT TRANSFER ACKNOWLEDGE (TA)
1) REMOVE DATA FROM D7–D0
2) NEGATE TA
PROVIDE VECTOR INFORMATION
REQUEST INTERRUPT
EXTERNAL DEVICE
TERMINATE CYCLE
MOTOROLA