Internet PLC Forum

Can someone tell me what is wrong with the following code:

'Get the Set Value of the timer and store in a variable

ElapsedTimeSVFor = getTimerSV(4)
ElapsedTimeSVRev = getTimerSV(5)

'Elapsed Time Forward Display

IF TESTIO(SBX_LSR)=0 '& TESTIO(SBX_LSF)=0 & TESTIO(LSF_LATCH)=0)
THEN
ElapsedTimeDisplay = ElapsedTimeSVFor - TIMERPV[4]
ELSEIF TESTIO(SBX_LSR)=0 & TESTIO(LSF_LATCH)=1
THEN
ElapsedTimeDisplay = ElapsedTimeSVFor - TIMERPV[5]
ELSE
ElapsedTimeDisplay = 0
ENDIF

I get a message:

Error:Syntax error, missing: "]" with the last square bracket after TIMERPV[4] highlighted?

Thanks

Hi Again!

I have been able to read bits over the MODBUS TCP/IP but I am having trouble writing from the HMI to the PLC.

For example I have r6 which I can read from using the address and function code as:

11030.

i.e. Function Code 1 followed by the Bit Address.

I tried to write to r1 using the same format i.e. 51025 but this give me an error.

I suspect that the following section from page 19-9 in the manual may be the reason:

“All the Nano-10 I/O bits are mapped identically to both the MODBUS “0x” and 1x space.  Although MODBUS names the 0x address space as “Coil (which means output bits) and the “1x” address space as “Input Status” (which means input bits only), the Nano-10 PLCs treat both spaces the same.  Some MODBUS drivers only allow you to “read” from the 0x space and “write” to 1x space but you still use the same offset shown on Table 14.1”

I am somewhat confused about the above statement.  I am trying to use Advanced HMI as the HMI programme and the MODBUS TCP driver will not accept addresses of the format 0-1025 or 1-1025.  So what would be the correct address to map to r1 on 1025 but in the “1x” space?

Confused…..

Hi there – I am looking for some pointers in figuring out MODBUS TCP/IP with the Nano-10.  I am new to the Nano-10 and TRI products in general however I am fairly familiar with PLC’s in general.  However I have never used any kind of MODBUS so I am a little bit confused how to implement this with the Nano-10.

I have been able to set up a test rig with a couple of Nano-10’s and I have downloaded a programme and I can monitor online and can see the programme operating nicely.  Now I want to get the Nano-10 to talk to a simple HMI interface over Modbus TCP/IP.

Where I am struggling is how to get the information from the ladder over the MODBUS TCP/IP link to the HMI.

Here is an example of what I mean:

I have a bit programmed as “FAULT” and uses a RLY output of “r9” in my ladder.

I intend the Nano-10 to be the server and the HMI to be the client.  What do I need to do at the PLC end to make “r9” so that this can be read by the HMI?

What would the MODBUS address of “r9” be?  Do I need to copy “r9” to a specific memory address than can then be accessed by the HMI?

I have read up on the READMODBUS and WRITEMODBUS but as far as I can understand these functions are for when the Nano-10 is used as the client and not the server?

I get the feeling I am just not getting something conceptually here?  I would be very grateful if someone can give me a few pointers in this?

Support!

Many thanks for the response – very much appreciated!

Regarding your comments on the outputs….I am using the two relay outputs so I assume that the contacts are isolated?

The other output I am using to switch via an interposing relay.

Thanks again!