LOGO and Nodered

Hello,

basically im trying to read the value of a counter in the PLC LOGO! and send it using node-red towards the dashboard. I've used the TSAP method to allow them to communicate, I've also used the absolute addresses in the correct form in order for the logo and node red to understand them, as you can see in the attachment all I/O are online. if i control the inputs of the plc they work.

my question is where is the counter value of the counter block stored in the PLC and how can i access it? should i connect it directly to the message payload or should i use a function in order to change how the message is recieved in node-red, in order to display the number of counts that is on my logo screen on my node-red dashboard.

You have to use the vm mapping, just map your counter actual value to VD0 to get the value over DBD1.DBD0, see attachment.

Regards, Scorp

Hello Scorp,

thank you for your time, i have already done that using Parameter VM mapping, there is an established connection and its online on node-red therefore therefore the absolute address is correct. After this step i want to extract the value of the counter and to send it to the dashboard, therefore after using the the S7 node i've connected it with a msg.payload but i don't recieve a value except for zero even after the counted number has changed. therefore this is my question is it correct to connect it directly to the msg.payload or should i use processing node (e.g Function) because i haven't been recieving any number except for 0. 

please check the attachment.

Sorry, but i have no knowledge of Node red. Have you any other actual variable or input/output, which is working or showing the correct status ? Bits, bytes, words or double words should work similar as status display. The difference is only the different length of the variables, e.g. DB1.X0.0, DB1,DBB0, DB1.DBW0 or DB1.DBD0. The actual counter value is an unsigned double integer (32 bit) between 0 and 999999.

Regards, Scorp

basically i have input values and they are all working and i can increase the value of the counter from nodered which means that the address's that i have used are correct. i think the problem is how nodered observes the counted number from the counter in the plc because the message payload that is read is always zero. I think it is a node-red issue. 

Thank you for your time

Not sure if you found it yet, but it is a DWORD value, so the variable is then called DB1.DINTxx

and not DB1.INTxx ( for a WORD )

Wherein xx is the address of the VM mapped block

Llene la mayor cantidad de direcciones correspondientes a Node-Red, para poder acceder a LOGO!, el archivo dentro del comprimido es de tivo .CSV

Este archivo puede ser importado desde Node-Red, espero que sea de ayuda.