1. System Overview
1.1 Introduction
P0.n
P1.n
Digital Peripherals
UART
Timers 0,
1, 2, 3
PCA/WDT
SMBus
Priority
Crossbar
Decoder
Crossbar Control
Port I/O Configuration
CIP-51 8051 Controller
Core
64/32/16 KB ISP Flash
Program Memory
256 Byte SRAM
4096 Byte XRAM
SPI 0,1
Power Net
VDD
GND
XTAL1
SYSCLK
System Clock
Configuration
External
Oscillator
Circuit
Precision
24.5 MHz
Oscillator
Debug /
Programming
Hardware
Power On
Reset/PMU
Reset
C2D
C2CK/RSTb
Wake
XTAL2
Low Power
20 MHz
Oscillator
XTAL3
XTAL4
VREG
Digital
Power
Analog
Power
Port 0
Drivers
Port 1
Drivers
Port 2
Drivers
P2.n
RTC
Oscillator
CRC
External Memory Interface
Control
Address
Data
Analog Peripherals
SFR
Bus
Comparators
+
-+
-
6-bit
IREF
IREF0
AMUX
10-bit
300ksps
ADC
Temp
Sensor
External
VREF
Internal
VREF
VDD
VREF
GND
Figure 1.1. Detailed EFM8SB2 Block Diagram
EFM8SB2 Reference Manual
System Overview
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