Texas Instruments CC2650DK 사용자 설명서
System
CPU
Cortex-M3
M
M
DMA
System Flash
128 KB
A
D
D
I
System RAM
20 KB
Security
subsystem
Radio
CPU
Cortex-M0
Bus Bridge
Modem, Frequency
Synthesizer, and
RF interfaces
Other
peripherals
L1 interconnect
L2 interconnect
RF Core
Bus Fabric
Analog/Digital Signals
Bus Master
M
M
M
M
M
Legend
RF Core
23.1 RF Core
The RF core contains an ARM Cortex-M0 that interfaces the analog RF and base-band circuitries, handles
data to and from the system side, and assembles the information bits in a given packet structure. The RF
core offers a high-level, command-based API to the system CPU (ARM Cortex-M3). The RF core can
autonomously handle the time-critical aspects of the radio protocols (802.15.4 RF4CE and ZigBee,
Bluetooth Low Energy, and so on), thus offloading the system CPU and leaving more resources for the
user’s application.
data to and from the system side, and assembles the information bits in a given packet structure. The RF
core offers a high-level, command-based API to the system CPU (ARM Cortex-M3). The RF core can
autonomously handle the time-critical aspects of the radio protocols (802.15.4 RF4CE and ZigBee,
Bluetooth Low Energy, and so on), thus offloading the system CPU and leaving more resources for the
user’s application.
The RF core has a dedicated 4-KB SRAM block and runs almost entirely from separate ROM memory.
23.1.1 High-Level Description and Overview
The RF core receives high-level requests from the System CPU and performs all the necessary
transactions to fulfill them. These requests are basically oriented to the transmission and reception of
information through the radio channel, but can also include additional maintenance tasks such as
calibration, test, or debug features.
transactions to fulfill them. These requests are basically oriented to the transmission and reception of
information through the radio channel, but can also include additional maintenance tasks such as
calibration, test, or debug features.
As a general framework, the transactions between the system CPU and the RF core operate as follows:
•
The RF core can access data and configuration parameters from the system RAM. This reduces the
memory requirements of the RF core, avoids needless traffic between the different parts of the system,
and reduces the total energy consumption.
memory requirements of the RF core, avoids needless traffic between the different parts of the system,
and reduces the total energy consumption.
•
In a similar fashion, the RF core can decode and write back the contents of the received radio packet,
together with status information, to the system RAM.
together with status information, to the system RAM.
•
For protocol confidentiality and authentication support purposes, the RF core is also able to access the
security subsystem.
security subsystem.
•
In general, the RF core understands complex commands from the system CPU (CCA transmissions,
RX with auto acknowledge, and so forth) and atomizes them into smaller subcommands without further
intervention of the system CPU.
RX with auto acknowledge, and so forth) and atomizes them into smaller subcommands without further
intervention of the system CPU.
shows the external interfaces and dependencies of the RF core.
Figure 23-1. Limited RF Core Overview with External Dependencies
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SWCU117A – February 2015 – Revised March 2015
Radio
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