1734-232asc

Hello all,

First time ASCII comms and I am currently trying to connect a Point I/O 232ASC card to a Keyence LK-G5000 laser displacement sensor via RS232C port.

Logix5000 v.20.01.00

I have the card and sensor wired as the manual suggests. I have the baud, parity, stop bits, and delimiters set as the manual suggests.

The keyence has a MS,01 [CR] command that is supposed to reply back with the current measured value but when I send this command the only thing that changes is the Receive.Status. It will change from 0 to 16. Receive records does not increment.

The keyence manual says it only needs the CR delimiter at the end and speaks nothing of a starting delimiter.

In the 232ASC tags, I enter the command like this.
Keyence:4:O.Data[0] - M
Keyence:4:O.Data[1] - S
Keyence:4:O.Data[2] - ,
Keyence:4:O.Data[3] - 0
Keyence:4:O.Data[4] - 1
Keyence:4:O.Data[5] - $r

Length set to 6.

One other thing is the Keyence manual specifies the SD (TXD) pin as an input and the RD (RXD) as an output. So I have it wired as SD->TX and RD->RX.

If anyone could give some advice as to if I have the command and length right, I would appreciate it. Like I said, I am not receiving anything back from the Keyence.

I just set one of these ASCII modules up for a special class ... I can get my notes from the lab later this weekend and maybe help ...

BIG QUESTION: how are you making the connection to the PLC? - by Devicenet - or by Ethernet - or by Controlnet ? ...

also BIG TIP: use HyperTerminal, etc. to get things working at each (both) ends of the cable - THEN start working with the PLC, etc. in place ...

Thanks Ron, the 232ASC module is on a 1734-AENTR ethernet.

I am unable to take the sensor offline as it is currently in use. The analog output of the unit is fritzy and we were going to try to use the RS232C in place of it.

FWIW, I can jumper the Tx to Rx on the module and not get a reply of the command I send.

New progress...

After testing the module with the jumper and finally getting solid results with the correct length, the keyence is now sending its values to the RS232.

I didnt actually recieve any commands back with the jumper installed until I changed the length arbitrarily to 20 which is the max characters setup. At this point I was out of ideas and crosseyed from reading through manuals and double checking settings. After testing some different lengths I ended back to my original length of 6 and it still worked. I changed the command and resent and received the command back. Everything was then working as it should seem.

Hooked the Keyence back up and set it to automatic transmission and got the data I needed.
From the testing I did, it did not matter if I set the length to 6,16, or 20. I received the command just as I sent it. Beats me...but it is working beautifully...for now.