Node-red-contrib-s7: all db data in one shot

Hi, I'm using node-red-contrib-s7 to connect S7-1200 PLC with no problem since a while.
Now the project is changing sensibly and I need to read all db which has more than 300 variable (every one second at least).
There is a way to read all db as bytearray in one shot? I have done several test with no success (I cannot change the PLC program).
Thanks