Silicon Laboratories Stepper Machine Especificações descarregar pdf (Página 22)

C8051F330/1

22 Rev. 1.1

1.6. Programmable Counter Array

An on-chip Programmable Counter/Timer Array (PCA) is included in addition to the four 16-bit general purpose

counter/timers. The PCA consists of a dedicated 16-bit counter/timer time base with three programmable cap

ture/compare modules. The PCA clock is derived from one of six sources: the system clock divided by 12, the system

clock divided by 4, Timer 0 overflows, an External Clock Input (ECI), the system clock, or the external oscillator

clock source divided by 8. The external clock source selection is useful for real-time clock functionality, where the

PCA is clocked by an external source while the internal oscillator drives the system clock.

Each capture/compare module can be configured to operate in one of six modes: Edge-Triggered Capture, Software

Timer, High Speed Output, 8- or 16-bit Pulse Width Modulator, or Frequency Output. Additionally, Capture/Compare

Module 2 offers watchdog timer (WDT) capabilities. Following a system reset, Module 2 is configured and enabled

in WDT mode. The PCA Capture/Compare Module I/O and External Clock Input may be routed to Port I/O via the

Digital Crossbar.

Figure 1.8. PCA Block Diagram

Capture/Compare

Module 1

Capture/Compare

Module 0

Capture/Compare

Module 2 / WDT

CEX1

ECI

Crossbar

CEX2

CEX0

Port I/O

16-Bit Counter/Timer

PCA

CLOCK

MUX

SYSCLK/12

SYSCLK/4

Timer 0 Overflow

ECI

SYSCLK

External Clock/8

1 2 ... 17 18 19 20 21 22 23 24 25 26 27 ... 203 204

Sem comentários

Silicon Laboratories Stepper Machine Especificações Página 22