OTA Programing

The OTA (Over-the-Air) programing API provide the capability of update the firmware from Azure cloud for IoT DevKit.

Assembly

OTAFirmwareUpdate.h

Summary

Methods

OTADownloadFirmware

int OTADownloadFirmware(const char *url, uint16_t *crc16Checksum, const char* ssl_ca_pem);

Download new firmware from the given URL.

Parameters

Type	Name	Description
const char*	[in] url	The URL to download firmware from.
uint16_t*	[out] crc16Checksum	Return the CRC-16 (XMODEM) checksum of the downloaded firmware
const char*	[in] ssl_ca_pem	Cert of the site of the given URL to ensure the connection is under a secure manner, default is NULL which means use cert of Microsoft Azure for TLS communication.

Return value

Return the size of the new firmware on success, otherwise return -1 if encounter network issue, return -2 if encounter external flash accessing issue.

OTAApplyNewFirmware]

int OTAApplyNewFirmware(int fwSize, uint16_t crc16Checksum);

Apply the new firmware, after reboot the device will update to the new version.

Parameters

Type	Name	Description
int	[in] fwSize	Size of the firmware.
uint16_t	[in] crc16Checksum	The CRC-16 (xmodem) checksum value of the firmware

Return value

Return 0 on success, otherwise return -1.

Sample Code

  // This can be customized according to the board type.
  uint16_t checksum = 0;
  int fwSize = OTADownloadFirmware(packageURI, &checksum);
  if (fwSize == 0 || fwSize == -1)
  {
    // Report error status, DownloadFailed
    return;
  }
  else if (fwSize == -2)
  {
    // Report error status, DeviceError
    return;
  }
  else if (fwSize != fwInfo->fwSize)
  {
    // Report error status, FileSizeNotMatch
    return;
  }
  
  // Applying
  if (OTAApplyNewFirmware(fwSize, checksum) != 0)
  {
    // Report error status, ApplyFirmwareFailed
      return;
  }