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Member
pesko
Posts: 13
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RS232 Master / Slave

[ Edited ]

Hi,

I am trying to use a RS232 master in combination with a RS232 slave module to acquire more than 16 channels from a RS232 data stream. The data is streamed with 10samples/sec per channel.

Dasylab is running with a sample rate of 10 and a block size of 1. In the master i have selected to output measurement data blockwise and selected the timebase to be Dasylab (10s/s block 1).

The master module works and sends data out 10 times per sec., but the slave module only sends data once per sec, and if look in the info area i can see that the slave module runs with a sample rate of 10s/s but the block size is 10 and it should be 1 to get all the data. can anyone explain why.

I am using Dasylab v12.0

Rgds.

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CJ_Butler__DASYLab_Pro
Posts: 837
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Re: RS232 Master / Slave

 

I'm sorry for the delay in responding... I've been out of the office unexpectedly.

 

I have to see if I can set up this scenario. How are the modules configured? Does each have a data request command? Are you using search strings? 

 

If you can just post the simple worksheet, it would help me understand how to set up a simulation, since I don't have hardware that will give me that many channels. 

 

By the way, I do believe you. The slave modules have sometimes exhibited problems.  I just need to set it up to understand.

 

 

- cj
Member
pesko
Posts: 13
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Re: RS232 Master / Slave

Hi CJ,

Attached you will find the worksheet.

There is no data request, a controller is streaming the data, and i just setup the search string. If i change the option to "output every measurement value immediately" it seems to be working with the slave module, the data then needs to to be synchronized with a signal adaption module where you ignore real time and the select the right frequency for the signals(10Hz), and then a seperate module to change the block size to 10. I am just afraid theat this configuration will use a lot of processor resources.

Rgds.

Pesko

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CJ_Butler__DASYLab_Pro
Posts: 837
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Re: RS232 Master / Slave

did you try the second setting, the "per line of data"? 

- cj
Member
pesko
Posts: 13
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Re: RS232 Master / Slave

Hi CJ,

I think that I tried outputting "per line of data" years ago, but I haven't tried it lately. As i remember the problem was that the output stops if all defined data aren't present, and that can happen occationally if the sender changes the number of channels.

/Pesko

Member
rolmale
Posts: 7
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Re: RS232 Master / Slave

Hello

I 'm trying to get the information way RS485 for DasyLab 11 but I cann't contact my device have communication Modbus RS485 RTU, when I tried conact it via RS232 monitor put the Hex code it cann't contact the device but if I use other software same Hex code it shows an good transsmition. What do you want think where is the errror.

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CJ_Butler__DASYLab_Pro
Posts: 837
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Re: RS232 Master / Slave

You should post new questions as new topics, not as a reply to an existing topic.

 

Modbus RTU is a very defined protocol. DASYLab 11 SP2 has the updated Modbus RTU module that should enable you to talk to your device. 

The RS232 module is not a good choice.

 

Download the update SP2 from www.dasylab.com

 

 

- cj