Hardware Reference
In-Depth Information
The CC2541 combines the following features:
• 8051 core with a 2.4 GHz radio
• 128 or 256 KB user-programmable flash memory
• 8 KB SRAM
One of the biggest advantages TI has over some of its rivals is that its BLE stack is feature
complete, essentially covering the entire 4.0 version of the Bluetooth Core Specification.
Some vendors have chosen not to implement certain infrequently used optional features,
whereas TI has made an intentional effort to reach a bit further in its functionality
coverage.
The CC2541 is also pin-compatible with the CC2540, which adds USB support to the
SoC. This potentially extends the lifespan of any design efforts around this chip family
with minimal additional design effort, since you can easily move your designs over to
peripherals that are connected to desktop or laptop PCs via USB connectivity.
TI takes design and testing seriously, and its RF chip families have a long design lineage.
It makes reliable chips using well-designed radios and provides significant design re‐
sources around those chips, for both hardware designers and firmware engineers. This
can be an important consideration for small companies without a lot of in-house RF or
embedded firmware design expertise.
One big weakness of the CC2541 is the relatively dated 8051 core driving its SoC, which
not only requires an expensive commercial compiler and IDE to use (
IAR Embedded
Workbench
), but also feels quite long in the tooth compared to more modern ARM
Cortex-M cores making their way into many other SoCs. This will likely change in the
near future, as SoC vendors feel greater pressure to move to newer cores, and TI is no
doubt well aware of the trend. It will be interesting to see how the company responds
moving forward.
Among the many development kits available for TI's CC254x family, the low-cost
CC2541DK-MINI (
Figure 5-2
) platform should enable peripheral designers to thor‐
oughly evaluate the development platform and SoC.
This kit includes all of the hardware you'll need to start working with the CC2541,
including a hardware debugger, a USB dongle that can act as a BLE master device on
your PC, and a key fob development board that can run your custom BLE code.
One attractive element of this development kit is that it closely resembles a real product,
with an injection-molded enclosure and two large, physical buttons that provide real
feedback during the initial development and debugging process. It's easy to overlook
these kinds of details in the early stages of product development, but they can help give
an idea of the real-world performance of a BLE device, even if some specifics (such as
operating range) will of course vary from one device design to another.
