Does MHD write to program area?

[fstbtstr]

Does MHD write changes to the program area? I.e., if I make some changes to some actual control routines and not just maps, will my bin with those changes get written completely or it will write only the maps? I'm specifically talking about N55e MHD.

 

[carabuser]

MHD only allows modifications to the calibration area. It's a safety to prevent people accidentally bricking their DME by corrupting the program.

 

[Itspeat]

I'd imagine that if you are using MHD+ functionality, it writes to the program space in memory as it is adding new features and probably changing some DME control routines in itself. Can't imagine how else they'd tap into the CANBUS, provide anti-lag, on the fly map switching, etc without doing that... but I could be wrong.

What are you trying to write yourself? Sounds interesting.

 

[fstbtstr]

Yeah, I emailed their customer support, and was told that at the moment, it's not possible to flash the program changes outside of what the MHD itself did. That's somewhat disappointing, but it does make sense for user protection. I was looking at MHD manual, and it does indicate that there're multiple write options you can choose for flashing a custom bin (full write, long write and map write), but sounds like it won't do anything for a custom bin with custom logic not done by MHD.
Anyhow, I'll try to use another tool which can write program area changes via OBD port, I don't want to remove the intake manifold and pull my DME out and write to it on the bench at the moment.
At the moment, I'm not planning to write anything interesting yet, just want to change a CCP CAN config. I want to see if I'm able to log any memory locations I want.

 

[fstbtstr]

very strange, posted a comment but somehow, it got flagged as waiting for moderator approval. Anyway, it's not a really important comment