Other Parts Discussed in Thread: AFE4490, CC2541
Hello,
Me and my colleage have been trying to interface AFE4490 with CC2541. We want to take pulse data from AFE4490 and send it to CC2541 through SPI and further process the data and send it to any bluetooth device. While trying to initialise the AFE4490 by writing its registers through SPI, we are not able to obtain any signal on the TXM and TXP pins.
Here are some of the specifications for the connections.
Power supplies to the AFE4490:-
RX_ANA_SUP = 3.3V
RX_DIG_SUP = 3.3V
TX_CNTRL_SUP = 5V
LED_DRV_SUP = 5V
AFE_PDNZ pin has been pulled high. We have connected the RESET pin of AFE4490 to a GPIO pin of the CC2541 where a low- going pulse has been applied. We checked the output voltages on the following pins :-
TX_REF = 0.75V
BG = 0.9V-1V
VCM = 0.9V
We could observe 4MHZ signal on the CLKOUT pin. Keeping the SPI baud rate to 2MHZ, we could even observe the SPI clock waveforms and signals on the MOSI pin during the initialization process.
But there is no signal on the TXM and TXN pin.
The code for the CC2541 has been attached.
It would really be of great help if anyone could suggest a solution.2728.AFE44x0.h
