C8051F02X Datasheet, PDF (27/272 Pages) Silicon Laboratories – 8K ISP FLASH MCU Family

C8051F020/1/2/3
1.5. Programmable Counter Array
The C8051F020 MCU family includes an on-board Programmable Counter/Timer Array (PCA) in addition to the five
16-bit general purpose counter/timers. The PCA consists of a dedicated 16-bit counter/timer time base with 5 pro-
grammable capture/compare modules. The timebase is clocked from one of six sources: the system clock divided by
12, the system clock divided by 4, Timer 0 overflow, an External Clock Input (ECI pin), the system clock, or the
external oscillator source divided by 8.
Each capture/compare module can be configured to operate in one of six modes: Edge-Triggered Capture, Software
Timer, High Speed Output, Frequency Output, 8-Bit Pulse Width Modulator, or 16-Bit Pulse Width Modulator. The
PCA Capture/Compare Module I/O and External Clock Input are routed to the MCU Port I/O via the Digital Cross-
bar.
Figure 1.10. PCA Block Diagram
SYSCLK/12
SYSCLK/4
Timer 0 Overflow
ECI
SYSCLK
External Clock/8
PCA
CLOCK
MUX
16-Bit Counter/Timer
Capture/Compare
Module 0
Capture/Compare
Module 1
Capture/Compare
Module 2
Capture/Compare
Module 3
Capture/Compare
Module 4
Crossbar
Port I/O
1.6. Serial Ports
The C8051F020 MCU Family includes two Enhanced Full-Duplex UARTs, SPI Bus, and SMBus/I²C. Each of the
serial buses is fully implemented in hardware and makes extensive use of the CIP-51's interrupts, thus requiring very
little intervention by the CPU. The serial buses do not "share" resources such as timers, interrupts, or Port I/O, so any
or all of the serial buses may be used together with any other.
Rev. 1.4
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