Motorola MC68302 User Manual page 7

TABLE OF CONTENTS (Continued)
Paragraph
Number
Title
Page
Number
3.1.4
3.1.4.1
3.1.4.2
3.1.4.3
3.1.4.4
3.1.4.5
3.1.5
3.1.6
3.1.7
3.1.7.1
3.1.7.2
3.1.7.3
3.1.7.4
3.2
3.2.1
3.2.2
3.2.2.1
3.2.2.2
3.2.2.3
3.2.3
3.2.4
3.2.5
3.2.5.1
3.2.5.2
3.2.5.3
3.2.5.4
3.3
3.3.1
3.3.2
3.3.2.1
3.3.2.2
3.3.3
3.4
3.5
3.5.1
3.5.2
3.5.2.1
iv
IDMA Operational Description ............................................ 3-10
Channel Initialization ................................................... 3-10
Data Transfer ............................................................. 3-10
Address Sequencing ................................................... 3-11
Transfer Request Generation ........................................ 3-12
Block Transfer Termination .......................................... 3-13
IDMA Programming .......................................................... 3-14
OMA Bus Arbitration ......................................................... 3-15
Bus Exceptions ................................................................. 3-16
Reset ......................................................................... 3-16
Bus Error ................................................................... 3-16
Halt ........................................................................... 3-17
Retry ......................................................................... 3-17
Interrupt Controller ................................................................. 3-17
Operation ......................................................................... 3-18
Interrupt Priorities ............................................................. 3-20
INRQ and EXRQ Priority Levels .................................... 3-20
INRQ Interrupt Source Priorities ................................... 3-21
Nested Interrupts ........................................................ 3-22
Masking Interrupt Sources and Events ................................ 3-22
Interrupt Vector Generation ............................................... 3-23
Interrupt Controller Programming Model. ............................ 3-23
Global Interrupt Mode Register (GIMR) ......................... 2-24
Interrupt Pending Register (IPR) ................................... 3-26
Interrupt Mask Register (IMR) ....................................... 3-27
Interrupt In-Service Register (ISR) ................................. 3-27
Parallel
1/0
Ports ..................................................................... 3-28
Port A .............................................................................. 3-28
Port B .............................................................................. 3-29
PB7-PBO .................................................................... 3-29
PB11-PB8 .................................................................. 3-31
1/0 Port Registers .............................................................. 3-31
Dual-Port RAM ................................................... ; ................... 3-31
Timers ................................................................................... 3-34
Timer Key Features ...........................................................
3~35
General-Purpose Timer Units .............................................
3~35
Timer Mode Registers (TMR1, TMR2) ............................ 3c36
MC68302 USER'S MANUAL MOTOROLA