The Collect Data function reads the desired result registers and sends the data based on the specified settings. This function works best with continuous conversion mode and does not configure the EVM or associated register settings. Collect mode started and stopped via the serial COM port, however the results are sent over the USB BULK channel. To use this mode, use the following format:

• Start collecting data format: collect timerPeriod collectFlags channelAddressIDs numDevices.
  • Where collect is always lower case, and each parameter is the decimal representation of the value in the following format:
    • timerPeriod
      • The timer delay used in the MCU to allow data collection sample sets (in µs, unsigned 32-bit value).
    • collectFlags
      • a byte of data that has a 1 to collect and a 0 to not collect each register value type, according to the following definitions (note to only use energy and charge flags when the device supports that, otherwise set to 0):
        • VBUS = 0b0100000
        • DIETEMP = 0b0010000
        • CURRENT = 0b0001000
        • POWER = 0b0000100
        • ENERGY = 0b0000010
        • CHARGE = 0b0000001
    • channelAddressIDs
      • I2C
        • This is the 4 LSBs of each address chained together, starting with the LSBs.
          • For example, if EVM 1 is on channel 0x41 and EVM 2 is on ox43, the value here is 0b00110001.
    • NumDevices
      • The number of EVMs chained together (1-4).
  • For example, to start data collection for VBUS, and DIETEMP every 3.156 ms, for two INA745s with EVM 1 address = 0x44 and EVM 2 address=0x46, the user needs to send: collect 3156 48 100 2.
    • For this example, the EVM returns the acknowledgment and state in JSON format:
      • {"acknowledge":"collect 3156 48 100 2"}
      • {"evm_state":"collecting"}
  • The USB BULK channel receives data in the format: frameID deviceNumID address registerSize data.
    • Where each parameter is the decimal representation of the value in the following format:
      • frameID (1 byte)
        • Always reads 0. Used to verify data is aligned.
      • deviceNumID (1 byte)
        • An ID number corresponding to the EVM number.
          • From the above example, this is 1 if reading from EVM 1 which had an address set to 0x44, and 2 if reading from EVM 2 which had an address set to 0x46.
      • address (1 byte)
        • The register address that was read from the device.
      • registerSize (1 byte)
        • The number of bytes that the following data has.
      • data (1 byte at a time)
        • The register data value, given in bytes with the most significant byte first.
• Stop collecting data format: stop
  • Where stop is always lower case.
  • The EVM returns the acknowledgment and state in JSON format:
    • {"acknowledge":"stop"}
    • {"evm_state":"idle"}