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How do I get Floating-Point values in a PLC5 or SLC processor from the Modbus module?

To view the floating-point value, the two 16-bit integers must be copied to a floating-point variable in the processor. For PLC and SLC processor, a COP command is used, with the source being the first integer value location, the dest being the F file location, and the len being ...

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What causes a conditional command to be issued?

A conditional command is useful when the same value does not need to be written to the end device continuously, but rather on change. A conditional write command is scanned based upon its poll rate (like all other commands).  The difference is that it will not be execut...

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How to configure more than 100 commands per port when using an MVI46-MCM, MVI69-MCM, or the MVI56-MCM as a Modbus master?

Master command list contains up to 100 individual entries. Event command control blocks may be used to send additional Modbus commands directly from theladder logic to one of the master ports....

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What is the purpose of the UseGuardBand/GuardBandTime or InterCharacterDelay parameters in an MCM module?

Due to timing variations in various Modbus devices, it is possible for a Modbus master to have problems sending write commands to the MCM slave port while having no issues with read commands.In such cases, the "Use Guard Band" and "Guard Band Time" parameters ...

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Baud rate entries greater than 32767 in ProSoft Modules

Since RSLogix uses signed integers, the highest positive value that can be entered is 32767. To avoid this issue, when specifying higher baud rates, Prosoftmodules only require the first 3 digits of the baud rate. e.g., to enter a baud rate of 38400, enter 384. Use 576 for 5...

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Where are the on-board jumper positions defined for my MVI module?

On bottom of the circuit board for any MVI products, you' ll find three jumper banks: COM1, COM2, and Setup.Each jumper position is labeled 232, 422 and 485....

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