I am testing now new release v0.34
First of all bkcmd=0 suppose to suppress all the errors returned but is ignored for this one:
It is not documented on itead website in returned error codes table, but I traced it down to be indication that the "ref compID" , providing page name as a part of component ID, but this page is currently not active. When I switch Nextion to this page, error '2' disappears.
So the problem is 2-fold
1. please provide this error code info on your website "nextion instruction set"
2. fix code to eliminate this return messages if bkcmd=0 to match the description on the same page.
This is important because the unexpected replies slow down the communication between MCU and Nextion. The more "ref" commands issued to the non-active page - the more system slows down.
There are work around steps but it would be much better to fix this.
Errorcode 0x02 is a call to an Invalid Component ID
Mine occurred when click t11,1 changed pages to another page, in which t11 was no longer valid to be called when the new page was loaded. But now we know what the Error code 0x02 is - now it just remains to be documented in the Nextion Instruction Set Return Data