Motorola MC68HC908AB32 - Contents; Introduction; Section 13. Programmable Interrupt Timer (PIT)

MC68HC908AB32 — Rev. 1.0 Technical Data
MOTOROLA Programmable Interrupt Timer (PIT) 221
Technical Data — MC68HC908AB32
Section 13. Programmable Interrupt Timer (PIT)
13.1 Contents
13.2 Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .221
13.3 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .222
13.4 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .222
13.4.1 PIT Counter Prescaler . . . . . . . . . . . . . . . . . . . . . . . . . . . .223
13.5 Low-Power Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .224
13.5.1 Wait Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .224
13.5.2 Stop Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .224
13.6 PIT During Break Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . .224
13.7 I/O Registers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .225
13.7.1 PIT Status and Control Register. . . . . . . . . . . . . . . . . . . . .225
13.7.2 PIT Counter Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . .227
13.7.3 PIT Counter Modulo Registers. . . . . . . . . . . . . . . . . . . . . .228
13.2 Introduction
This section describes the programmable interrupt timer (PIT), which is
a timer whose counter is clocked internally via software programmable
options. Figure 13-1 is a block diagram of the PIT.