MC68HC12 Datasheet, PDF (137/478 Pages) Motorola, Inc – The MC68HC912DT128A microcontroller unit (MCU) is a 16-bit device composed of standard on-chip peripherals including a 16-bit central processing unit

Technical Data — MC68HC912DT128A
Section 10. Resets and Interrupts
10.1 Contents
10.2 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137
10.3 Exception Priority . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138
10.4 Maskable interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .138
10.5 Latching of Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .139
10.6 Interrupt Control and Priority Registers . . . . . . . . . . . . . . . . .141
10.7 Interrupt test registers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142
10.8 Resets. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .143
10.9 Effects of Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145
10.10 Register Stacking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147
10.2 Introduction
CPU12 exceptions include resets and interrupts. Each exception has an
associated 16-bit vector, which points to the memory location where the
routine that handles the exception is located. Vectors are stored in the
upper 128 bytes of the standard 64K byte address map.
The six highest vector addresses are used for resets and non-maskable
interrupt sources. The remainder of the vectors are used for maskable
interrupts, and all must be initialized to point to the address of the
appropriate service routine.
MC68HC912DT128A — Rev 4.0
MOTOROLA
Resets and Interrupts
Technical Data
137