nRF93M1 supports two over-the-air firmware-update transports and UART or USB based production-line flashing path. Each over-the-air path delivers cryptographically signed images that are verified against the hardware root-of-trust before activation.
Over-the-air firmware update
| Path | Description |
|---|---|
| HTTP(S) FOTA | AT%HTTPFOTADL downloads an image directly from a host-supplied URL. TLS security context, content-type, and transport parameters are set through %HTTPCFG. |
| nRF Cloud FOTA | AT%NRFCLOUDFOTA with operations: 0 check host-application OTA, 1 download host-application chunk, 2 check modem firmware, 3 check and apply modem firmware, 4 clear cached URL. Chunks are Base64-encoded with CRC-16/CCITT-FALSE framing. |
Production-line firmware updates
For production-line and bring-up, the module accepts firmware over UART using the Nordic download tool. The download agent boots at 115 200 bps and can be set to 3 Mbps for faster transfer.
Security guarantees
All firmware images are cryptographically signed. The signature is verified during the boot stage against the hardware root-of-trust. Images that fail verification are rejected and the module rolls back to the previously known-good image. See the Security chapter for details.