Software download of the project results in 'ERROR sending cmd 85'

[obscuresc]

Hi,

I am using EcoStruxure Machine Expert - HVAC v1.6.0.

On one of my projects I routinely receive an error during a download all of the project

Spoiler

SendPLCCommand: ERROR sending cmd 85
M172 07-18 I/Os: ERROR reloading HMI!

The PLC will sit, 'Not Running, until I use the 'Reboot Target' button.

How do I begin to solve this issue?

Is there a place that these errors live in documentation so that I know what to look for?

Cheers.

[FedericoM]

Hi,

this error occurs when the PLC is not able to reload the code written in flash at the end of the download.

In this case it seems related to the local hmi code.

I would investigate if you have some functions using the flash memory during the boot/init phase.

[otrotabi]

Hello Federico,

Would you mind explaining exactly what that means ? What is flash memory and how would you use it ? 

Thanks

[obscuresc]

Thanks @FedericoM.

I use 'sysWriteParUINT' to configure defaults on the IEC side, this occurs during the init stage.

This is so I can reused the values in code, or apply limits globally.

Is there a way that I can keep these functions still in the init stage?

Is there documentation explaining this form of error code?

[FedericoM]

sysWritePar*() functions update the EEprom, I don't think they can create these problem unless you are really using a lot of them (the execution time of n sysWritePar is 5ms x (n-1)).

With flash memory I mean the internal storage of the M172, what you can see via ftp.

If you have a lot of files saved in the internal flash (application, hmi + webserver), the problem could occur if the space available is not enough to store the file you are downloading....

[obscuresc]

@FedericoM I have 25 sysWritePar calls at the moment, resulting in a delay of 120ms. They won't run all the time, they're primarily used to EEPROM defaults using IEC side values. So generally, will blocking calls cause this issue? Is there a time limit that the init stage needs to be shorter than?

[FedericoM · Accepted solution]

These are not causing any issue (5ms are needed when the function really update the eeprom). Better to run them in background, if in Timed it is better to keep the execution time lower than 50-60ms.

Background execution time could be even in the range of seconds.