2.1 2.2. crash course on the cc2500

The CC2500 is the radio chip on the eZ430-RF2500. It functions in the 2400- 2483.5 MHz frequency band and provides an excellent option for WSN applications because of its low-power characteristics. This chip has 20 pins:

• 2 for connecting a (mandatory) 26MHz external crystal oscillator;
• 2 for connecting the antenna;
• 10 for powering the chip;
• 6 for digital communication with the MSP430 (to be detailed in section 3.3)

The chip contains 47 registers to configure operating frequency,modulation scheme, baud rate, transmission power, etc. Because these registers are erased during powerdown, the MSP430 should configure all of them at startup. 13 commands allow the MSP430 to control the state of the CC2500 (transmit, power down, receive, . . . ).The CC2500 follows a state diagram, as detailed in the CC2500, Low-Cost Low-Power 2.4 GHz RF Transceiver datasheet.

In practice, Texas Instruments provides some code which hides the low-level details of the CC2500 behind a higher level API. These drivers are part of the SimpliciTI project , available for free. We will use these off-the-shelf drivers in this tutorial.