Print Page - IDA xrefs after loading a2l

I got some ori files with a2l, I wrote a script to load them on IDA, and it looks like everything makes sense - the data offsets look like they are resolved correctly.

One thing that I can't understand is why there are no x-refs from the data offsets defined by the a2l from the code section.

For example, from IDA:

Code:

ROM:001C0678 05          NetMng_ctGEMOOffDec_C:.byte    5
ROM:001C0679 03          NetMng_ctGEMOOffInc_C:.byte    3
ROM:001C067A 80          NetMng_ctGEMOOffMax_C:.byte 0x80
ROM:001C067B 05          NetMng_ctGEOffDec_C:.byte    5
ROM:001C067C 03          NetMng_ctGEOffInc_C:.byte    3
ROM:001C067D 80          NetMng_ctGEOffMax_C:.byte 0x80
ROM:001C067E 05          NetMng_ctMOGEOffDec_C:.byte    5
ROM:001C067F 03          NetMng_ctMOGEOffInc_C:.byte    3

There are a lot of CHARACTERISTICs, but no x-refs at all from the code.

Does anyone know the explanation for that? how does this data reference from the code?

It does indirect addressing via custom bosch library functions.

They also differ from software project to software project.

It can be summarized like: Large function groups have an own base address which is a memory location or a register.
Access to calibration area is then done with an indirect load/move which loads base of function group and map offset. Specific functions of that function group can use 8 Bit addresses then which saves memory and calculation time.

So no easy cherry picking here :)

NefMoto

Technical => Reverse Engineering => Topic started by: HexTrain on August 20, 2019, 03:18:11 AM