ncs dfu over ble，no enough flash space for two slot

[Clever Huang]

hi，

i have just to develop an appilcation with NCS 1.9.1 of nrf52840. Now I have tried to activate DFU and I had to realize that the image size is too large（490k without mcuboot）beacuse of my application supported multiprotocol. as i know, mcuboot must use two slot for dfu over ble (is right?).

Is it possible to use nrf5 boot to upgrade  applications of single slot in ncs?  Can provide some advice or reference design to slove dfu when image too large with ncs? 

thanks ！

[dejans]

Hi,

i have just to develop an appilcation with NCS 1.9.1 of nrf52840. Now I have tried to activate DFU and I had to realize that the image size is too large（490k without mcuboot）beacuse of my application supported multiprotocol. as i know, mcuboot must use two slot for dfu over ble (is right?).

Each flash area contains primary and secondary image slot. Image is run from the primary slot. Generally, in order to run the image from the secondary slot, that image needs either to be copied to the primary slot or primary image can be overwritten by the secondary image as described in image slots. With BLE, you would use 2 application slots when performing firmware upgrades.

Is it possible to use nrf5 boot to upgrade  applications of single slot in ncs?  Can provide some advice or reference design to slove dfu when image too large with ncs? 

Multiprotocol applications can be bigger with NCS than with nRF5. You could consider using an external flash if your image becomes too large.

Best regards,
Dejan