Hi All,
I am trying to use a MicroLogix 1200 PLC to read and write ASII data to another device. I have run into two problems which may or may not be related.
First my ARD and AWT blocks cannot be enabled at one time. Ideally my ARD block would be enabled all the time reading in new ASCII data and the AWT block would be enabled only when a new string needs to be written. The AWT block freezes up whenever the ARD block is enabled. I do have a separate register defined for the AWT and ARD functions.
The ultimate goal of this project is to send out an ASCII string from the PLC and then wait for a response from the other device. When my laptop is connected to the other device I can send out the ASCII string (using HyperTerminal) and the response comes back to the laptop just as I would expect. But when using the PLC, I send out the ASCII string from the PLC but the response is not seen from the other device.
Is there anything I need to do to prepare the PLC for receiving the ASCII data after an ASCII write? Thanks for your help.
Kevin
I am trying to use a MicroLogix 1200 PLC to read and write ASII data to another device. I have run into two problems which may or may not be related.
First my ARD and AWT blocks cannot be enabled at one time. Ideally my ARD block would be enabled all the time reading in new ASCII data and the AWT block would be enabled only when a new string needs to be written. The AWT block freezes up whenever the ARD block is enabled. I do have a separate register defined for the AWT and ARD functions.
The ultimate goal of this project is to send out an ASCII string from the PLC and then wait for a response from the other device. When my laptop is connected to the other device I can send out the ASCII string (using HyperTerminal) and the response comes back to the laptop just as I would expect. But when using the PLC, I send out the ASCII string from the PLC but the response is not seen from the other device.
Is there anything I need to do to prepare the PLC for receiving the ASCII data after an ASCII write? Thanks for your help.
Kevin
