ModbusTCPSlaveユニット

Last updated: March 9,
2021 Created: February 9, 2021

I thought I'd prepare a template for the ModbusSlave device.
*The board size has been modified in consideration of Eagle's limitations.

There are many I/O units with fixed functions in the world. Some people think that this one is easier to use. However, I thought it would be nice to have a device that can reach itchy places. * It is similar to the Modbus model of industrialshields Inc.
It is handled by a mechanism that skips if it is not connected by preparing representative I/O in advance.

I thought about the benefits of Modbus devices. Because of standardized communication specifications, client software can be covered by general-purpose products.
It can be controlled with free software on iPhone and Nexus 7 beyond the barrier of OS. *However, it is not intuitive to use.

The power supply for control is covered by the supply of 5V500mA from USB. Contact input/output supports DC24V. If ON/OFF control of AC power supply is required, it is realized through a relay unit.
ADC (ADS1125) handles 0V to +10V with 16bit resolution. 2ch will be prepared.
DAC (MCP4725) handles 0V to +5V with 12bit resolution. 2ch will be prepared.

 

 

 

 

 

(01) Coil contact 16 points Insulated output by photo coupler (open collector) It is assumed that 24V is applied.
* 32 points (2 words) are reserved internally, but 16 points are used as external terminals.

(02) Read contact 16 points Photo coupler input Assuming a 24V input, a 22KΩ limiting resistor is inserted.
* 32 points (2 words) are reserved internally, but 16 points are used as external terminals.
　It also displays alerts for input register values.

(03) Holding register 16 words You can input and set the alert setting value, DAC output value, counter setting value, etc. for the input register value.

(04) Input register 16 words Displays device information and specific input values