mc68ec020 Freescale Semiconductor, Inc, mc68ec020 Datasheet - Page 4

• Manufacturer Part Number: mc68ec020
• Description: Microprocessors
• Manufacturer: Freescale Semiconductor, Inc

9/29/95
Paragraph
3.12
3.13
4.1
4.2
4.3
4.3.1
4.3.2
5.1
5.1.1
5.1.2
5.1.3
5.1.4
5.1.5
5.1.6
5.1.7
5.2
5.2.1
5.2.2
5.2.3
5.2.4
5.2.5
5.2.6
5.2.7
5.3
5.3.1
5.3.2
5.3.3
5.4
5.4.1
5.4.1.1
5.4.1.2
5.4.1.3
5.4.2
5.4.3
5.5
5.5.1
viii
Number
Power Supply Connections ..................................................................... 3-7
Signal Summary...................................................................................... 3-8
On-Chip Cache Organization and Operation .......................................... 4-1
Cache Reset ........................................................................................... 4-3
Cache Control ......................................................................................... 4-3
Bus Transfer Signals............................................................................... 5-1
Data Transfer Mechanism....................................................................... 5-5
Data Transfer Cycles .............................................................................. 5-25
CPU Space Cycles ................................................................................. 5-44
Bus Exception Control Cycles................................................................. 5-53
Cache Control Register (CACR) ......................................................... 4-3
Cache Address Register (CAAR) ........................................................ 4-4
Bus Control Signals ............................................................................. 5-2
Address Bus ........................................................................................ 5-3
Data Strobe ......................................................................................... 5-4
Data Buffer Enable .............................................................................. 5-4
Bus Cycle Termination Signals............................................................ 5-4
Dynamic Bus Sizing ............................................................................ 5-5
Misaligned Operands........................................................................... 5-14
Effects of Dynamic Bus Sizing and Operand Misalignment ................ 5-20
Address, Size, and Data Bus Relationships ........................................ 5-21
Cache Interactions .............................................................................. 5-22
Synchronous Operation with DSACK1/DSACK0 ............................... 5-24
Read Cycle .......................................................................................... 5-26
Write Cycle .......................................................................................... 5-33
Read-Modify-Write Cycle..................................................................... 5-39
Interrupt Acknowledge Bus Cycles ...................................................... 5-45
Breakpoint Acknowledge Cycle ........................................................... 5-50
Coprocessor Communication Cycles .................................................. 5-53
Address Strobe .................................................................................... 5-3
Data Bus.............................................................................................. 5-3
Bus Operation ..................................................................................... 5-24
Bus Errors ........................................................................................... 5-55
TABLE OF CONTENTS (Continued)
Interrupt Acknowledge Cycle—Terminated Normally ...................... 5-45
Autovector Interrupt Acknowledge Cycle ......................................... 5-48
Spurious Interrupt Cycle .................................................................. 5-48
SECTION 1: OVERVIEW
On-Chip Cache Memory
M68020 USER’S MANUAL
Bus Operation
Section 4
Section 5
Title
UM Rev.1.0
MOTOROLA
Number
Page