Clarification on DFU

[JohnBrown]

Just want to check that my understanding is correct:

I have ported/migrated my app from SDK 6 to SDK 9, merely because I want to use the DFU facility. However, I have read that the single bank DFU is no longer compatible with the PC based MCP, and one has to use the phone based MCP. Also, I think I read that the single bank DFU code has not been revised/tested for SDK9, so I will need to do some tweaking. The reason I want to use the single bank mode, before you ask, is because the modules we are using contain rev 2 silicon(I have read all the hardware differences, and am of the opinon that none of them are likely to concern me) and thus have smaller flash memory. So what I'd like to know is: Are the phone-based versions of MCP likely to support single bank DFU in the future? Will it be fairly easy to tweak the single bank DFU bootloader code to run with SDK9?

BTW, I am not looking for "butonless" DFU operation.

[Hung Bui]

Hi JohnBrown,

On SDK v9.0 you can simply replace the file dfu_singIe_bank.c with file dfu_dual_bank.c and you should have BLE single bank DFU. This is not official tested and released but we tested in Techsupport and it worked fine here.

Note that chip revision 2 and 3 doesn't have the difference in ROM size. You have both 128 variant and 256 variant. To check which variant your chip is, have a look here.

I'm not sure where you read that current MCP on PC doesn't support single bank update. It was but with the introduce of the init packet, it should be ok now. On the DFU master side, it's transparent that the bootloader uses single bank or dual bank.

[JohnBrown]

Yes, my own internal memory is running out of space! The version 2 chip does indeed have 256K. As far as where I read that the current MCP on PC doesn't support single bank, I read it in your DFU FAQ, but on re-reading it, I see that it may refer to an older SDK/MCP. Thanks, as always, for the helpful response.