Only one CanMap can be saved to flash

[jsphuebner]

Currently only one flash location can be specified for saving CAN mappings to. In addition, both CanSdo and TerminalCommands only allow saving one map as well.

[zacck]

@jsphuebner I would like to see if I can use this as an inroad to contributing to open inverter firmware, could you describe an ideal solution?

[jsphuebner]

There is the simple method of modifying CanMap::GetFlashAddress() to return CAN1_FLASH if the device in use is CAN1 and otherwise CAN2_FLASH.

The other method would be to refactor flash saving altogether. It bugs me that there is a hardware dependency in the otherwise hardware independent CanMap class.

So there could be a Flash class that somehow manages flash pages in a backward compatible manner. An instance of that class can then be passed to all modules (CanMap and Params basically) that save things to flash

[zacck]

I’m going to do some reading based on this and get back to you, would  you mind assigning this to me please. I’ll be proactive and get it to the finish line. 

[zacck]

@jsphuebner Ok I have looked at this, I think the change to CanMap::GetFlashAddress() will be easy, then we can open a ticket to refactor flash saving. I'll do a small PR quick now

[zacck]

wait related question, as I am looking where does one choose which CAN interface to use? I wonder is it as simple as checking whether CAN1_BLKNUM or CAN2_BLKNUM is the selection from hwdefs?

[jsphuebner]

I just looked around. You can't find out. It's in the constructor of Stm32Can.

Might be easier to increase a static counter every time a new CanMap() is constructed and pick the appropriate BLKNUM with it

[jsphuebner]

Also note not every CanMap is saved. E.g. in FlyingAdcBms there is an internal CanMap which is rebuilt at startup