undercontrol

READ_VAR and WRITE_VAR are a couple, the purpose is definitely to read and write messages (Modbus?? - not sure). SEND_REQ on the other hand is to send a request to another party. The request might be a read request, a write request, a diagnostic request, .... depends on the request code you put in the syntax's parameters. Hope this helps

You could upload it in public ftp, like megaupload.com,....

Use "Register" function block (%Ri). There are 2 modes available, FIFO and LIFO.

As far as I know, it's programming cable for Modicon 984 PLC which is obsolete now.

You're gonna need Modbus PCMCIA card on the Premium side (TSXSCP114) and also Modbus port on Twido side. Then you can use READ_VAR or WRITE_VAR function from PL7 Pro to read/write message to Twido.

For Modicon Quantum, yes it's integrated on the CPU. But for Modicon Premium (TSX Premium) and Micro (TSX Micro), Unitelway is the integrated one, meanwhile Modbus will be available through additional card.

The answer to question 1 and 2 is using SEND_REQ function, if you d/l the manual you'll be able to find all the parameters you need to fill inside that function. On "how to connect PLC using ladder?", what do you mean connect here?? is it communication?? If it is then the answer is the same as Q 1 & 2.

I'm looking for 90-30 hot backup manual. Searched the GE web, got nothing!!! Searched "G", also nothing!!! Is 90-30 considered old???

You could use it directly, but it's normally recommended to store them to the memory.

As far as I know, you can not!!!

Well, TSX Micro supports 4 communication protocols : Unitelway, FIPWAY, Modbus and TCP/IP. For Unitelway, it's integrated by TER port but for the others, you've got to add comm. card, especially TCP/IP you have to add one module called TSX ETZ 410/510.

You could Unitelway (using TER port) or Modbus (additional card required) or TCP/IP (additional TSXETZxxx required).

Are u the one who posted this on control.com?? Anyway, you could click on "Tools" then choose "Library" then it'll give you a new window opened with variations of function available like communication, math,.... also PID. For PID function, you choose "Process Control" on the left side window then it'll give you options for PID or PWM. For the parameter setting, you could adjust it through the window below. Hope, this helps!!

Are u using IBM laptop?? If you are, make sure you have activated COM port from BIOS and this means, you go to the BIOS and check the COM port status. It sounds weird but it's true, coz IBM laptop default setting for COM port is unactive, though you can still use it for other serial comm but it's not gonna work on this case.