Texas Instruments CC2520, User Manual

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Q4 The MSP-FET430UIF should be able to power the CCMSP-EM and SmartRF05EB
when connected to the JTAG connector, but it doesn’t seem to work. Why?
A4 Place the jumper on header P14 in position FET (short circuiting pin 2 and 3).
Q5 When powering up the evaluation board, the LED D6 starts blinking. Why?
A5 If the blink frequency is 1 time per second, the boot loader has entered a forced boot
recovery mode (set during programming of the device). Power off the system and turn it
back on to start the application.
If the blinking is more rapid (10 times per second) the boot loader could not find a valid
application in flash. Use SmartRF Studio or SmartRF Flash Programmer to program a
new firmware on the board.
Q6 How can I measure the current consumption of the radio on the EM?
A6 The easiest way to measure current consumption of the chip in various modes is to
connect the EM directly to the SmartRF05EB and disconnect everything on the board
that consumes power by removing all jumpers on P1 and P4. The only jumpers needed
on P1 are the four SPI signals (CS, SCLK, MISO and MOSI) and one for the CC2520
VREG enable signal (DBG_DD). On P4, only the jumper for the EM_RESET signal is
required. Set the jumper on header P10 in position 1-2 (disable RS232 level converter)
and remove jumpers on P13, P14 and P19. Connect the ampere meter between the two
pins on P15 (V_EM).
Use SmartRF Studio to set the radio in different modes (RX, TX, etc.).
The same approach can be used when powering the CCMSP-EM + CC2520EM from
the EB. In this case, only the jumper for the EM_RESET signal on P4 is required.