Include onboard memory storage ($700 USD)

[josancamon19]

Is your feature request related to a problem? Please describe. Include onboard memory storage so that the user by just having the device on his neck, never loses a single audio byte of information.

Describe the solution you'd like

• This should include hardware update, and instructions, on how to solder/add the memory component + details on the component.
• This should include firmware update, so that the audio bytes are sent and stored and if not received, it should remove the bytes from the memory.
• This should include a functionality when the app connects again, it should send whatever bytes are in the storage to be processed in the app, once the processing happens, it should clean the audio bytes from storage.

This solution includes hardware, firmware, and flutter.

[Gashpid]

Hey, I’m gonna take this feature.

[josancamon19]

Assigned to Gashpid

[josancamon19]

Redundant local storage

This solution integrates a microSD memory to provide redundant storage on the device. The redundant storage ensures that the audio files are temporarily saved on the microSD until it is confirmed that they have been correctly transferred to the mobile application. Once the transfer is validated, the data stored on the microSD is deleted, thus ensuring efficient and secure information management. This feature uses a microSD module that operates via SPI, functioning as a bridge between the “XIAO-nRF52840 Sense” board and the micro-SD memory. A notification service is also added to the mobile application to alert if the delayed data has arrived correctly. ## MicroSD Card Module Pin Configuration - SPI

The micro-SD card module communicates via the SPI communication protocol. You can connect it to the XIAO-nRF52840 Sense using the default SPI pins. You can buy this module in [Amazon](https://www.amazon.com/RedTagCanada-Storage-Expansion-Soldered-Arduino/dp/B09LTMLJ12/ref=sr_1_61?crid=186EM4TGBRTT&dib=eyJ2IjoiMSJ9.ysWkCOQcBTdneiBpSvvAKKrtj7srmVoT71imrzeFa0enSmZvw0bG4MnVgIHU80dJ1zWteuQVzG4TlX2TxajJ8cVh79vZ1S1Eu3v5B0XQIuI-qvzZg566tzu60kRMY-mrgCmq7vkAS5yNwVG-lAFufuAdS2GNjGKbPUImbbQkh58zZ5YdNiGHNQXyScVS9l3o.81e3AigkNOWHioavXqN1PWDc-NdvahtwwMaEmpgkarc&dib_tag=se&keywords=micro%2Bsd%2Bcard%2Bbreakout&qid=1719634567&sprefix=micro%2Bsd%2Bcard%2Bbre%2Caps%2C210&sr=8-61&th=1) | Pin | SD Card Module | XIAO-nRF52840 | |-------|----------------|---------------| | 1 | 3V3 | VDD | | 2 | CS | P1.12 | | 3 | MOSI | P1.15 | | 4 | CLK | P1.13 | | 5 | MISO | P1.14 | | 6 | GND | GND | ## Preparing the microSD Card Para hay que asegurarse que la tarjeta microSD tenga el formato FAT32. Puedes usar el software [SD Card Formatter](https://www.sdcard.org/downloads/formatter/) (compatible con Windows y Mac OS).