M172 BIOS maintenance questions

[obscuresc]

Hi,

I have a project for 668p14 and hardware running 668p13 BIOS. I'd like to avoid updating the BIOS as the PLC is in the field and I have an unstable connection to it. Is there compatibility issues in this scenario?

Also, if I were to update the BIOS over the internet, are all IP parameters maintained so I can still access the PLC after the update?

Can I update the BIOS by uploading a BIOS file via FTP?

Thanks.

[FedericoM · Accepted solution]

Hello,

a newer project target doesn't run on an old bios if the project uses a new target block (it could happen) or the size of a target variable has been changed (we do it only if it is really necessary).

If the project is not compatible, it will not start.

You are clearly missing all the bug fixing introduced by the newest bios.

Bios update procedure does not change any parameter.

Bios can be updated only by serial or pendrive (no ftp)

[obscuresc]

@FedericoM when you say 'if the project is not compatible [with the hardware BIOS], it will not start', can you provide documentation on what this looks like?

[FedericoM]

Let's make an example: suppose that in the bios version 596.17 the target variable xyz has been added.

If you use this variable in your code and compile connected to a bios 596.16, you will get a compiler error related to xyz not defined on the target.

If you make a refresh current target or compile connected to 596.17, you will be able to compile.

If you create files for USB pendrive, they will work on 596.17, on previous bios version you will see PLC not loaded on the embedded display

[obscuresc]

@FedericoM thanks!