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AFE4300-EVM REV B : UART Problems with PC Serial Program.

elio kim
Prodigy 20 points
Other Parts Discussed in Thread: AFE4300, AFE4300EVM-PDK

Hello,

I have recently purchased  a AFE4300_EVM REV B board and the board works well with AFE4300 Device GUI provided by TI.

So, first of all, I have tried to control the board with my serial program about a reset command. As a result, the board didn't respond to the reset command.

Below are the test conditions.

1. my serial setting (57600 baudrate / data 8 bit / No parity / stop 1 bit / hardware flow control : none ) : serial open OK.

2. For Reset command, I sent  '0x72 0x73 0x74 0x3F'  according to 4150.Message Communication Protocol - AFE4300EVM-PDK.pdf.  : there is no response.

For reference, I checked if the reset command packets (0x72 0x73 0x74 0x3F) are outputted correctly with an oscilloscope.  I think the h/w is ok.

Could you help me solve this situation ?

In addition, is the latest version of a firmware  AFE4300EVMPDKFWSRC-1.0 ? If no, I'd like to get the final version.

Thanks in advances.

Elio

  • 0
    TI__Mastermind 49926 points
    Hi Elio,

    We have received your inquiry regarding the AFE4300EVM and hope to have some answers back to you shortly.
  • 0
    TI__Mastermind 49926 points
    Hi Elio,

    The response from the reset command (rst?) is a line feed and a carriage return (0x0a 0x0d)

    You may want to read the register address 1 (r01?). After reset, the default value in register 1 will be 0x01C3
    Following will be the response 0x20 0x30 0x78 0x30 0x31 0x43 0x33 0x0a 0x0d

    The AFE4300EVMPDKFWSRC-1.0 is the latest firmware version.
  • 0 in reply to Praveen Aroul
    Prodigy 20 points

    Hi Praveen,

    Thanks for your response. My serial program works well with your guide. 

    In addition, currently I obtained a ADC value about a 700 ohm with 50KHz, 64SPS and ADC_MEAS_MODE as A1,A2 differential(000). The ADC Value is 0x23db(decimal 9179) (two's complement format). 

    (1)   Is the ADC Value about a 700 ohm correct ?

    (2)   Eventually, I'd like to know how to calculate the voltage level with the ADC Value, the Vref  (1.7[V]) and ADC 16-bit.

    Regards,

    Elio

  • 0 in reply to elio kim
    TI__Mastermind 49926 points
    Hi Elio,

    The ADC volts to codes conversion formula is:
    ADC data (volts) = (ADC codes in two's complement format * Vref ) / 2^15
    where Vref = 1.7V

    For the ADC value of 23DBh (9179 decimal), the ADC data (volts) is about 476 mV.

    I do not follow your question about 700 Ohm. Are you referring to measuring the ADC codes of 9179 for a 700 Ohm resistor and for the AFE settings you have listed? If that is the case, you will need to do calibration with a known resistor and then use the proportionality factor to calculate the unknown impedance.