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INTRODUCTION RS485 TO WIRELESS
The NCD RS-485 to Wireless Adapter converts data in both direction between Wireless and RS-485
communications. Inside the modem, you will see a small module, which actually handles the conversion
process. This documentation will reference this module and all applicable jumper settings.
There are 3 versions of this modem, which will be covered in this guide. The communication protocols are
slightly different for each version. We will start the guide by covering the hardware, and then move on to
protocol for all 3 versions. Please note this guide will discuss commands in hex values ONLY.
Also, please note the default RS-485 Communications Baud rate is 9600. We suggest using the default settings
for best results.
Getting to Know NCD RS-485 Node Modules
NCD RS-485 Node modules are a modular technology, allowing most NCD devices to be retrofitted with RS-485
communication capabilities. Node modules have a number of options an
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Summary of Contents for NCD RS-485
- Page 1 We will start the guide by covering the hardware, and then move on to protocol for all 3 versions. Please note this guide will discuss commands in hex values ONLY. Also, please note the default RS-485 Communications Baud rate is 9600. We suggest using the default settings for best results.
- Page 3 NCD Node modules are preconfigured for RS- 485 communications at 9600 baud. Node modules communicate to the host device at 57.6k baud by default. Baud rate settings are programmable via RS-485. The C jumper must be installed for configuration.
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Page 4: Changing Baud Rates
Changing Baud Rates Change the USART Baud Rate Send the Following Bytes via RS-485: 9600 Baud USART: F3, 00, 25, 80 19,200 Baud USART: F3, 00, 4B, 00 38,400 Baud USART: F3, 00, 96, 00 57,600 Baud USART: F3, 00, E1, 00... -
Page 5: Factory Reset Procedure
Note: If the bus length exceeds more than 5,000 feet, users may experience data corruption. Standard Version Communications Protocol The Standard Version of this device communicates raw data between the Digi XBee module and the RS-485 link. This version is ideal for desktop computers that have the resources to properly generate and decode Digi API communication frames. - Page 6 The AutoEncoder version will wrap up and unwrap all wireless data and convert to RS-485 data. There is a speed penalty for this conversion, so it is slower than the Standard Version at the expense of ease of use.
- Page 7 7E 00 11 90 00 13 A2 00 41 8C 58 B6 FF FE C2 7C 00 00 FF FF A6 RS-485 Serial Settings – AutoEncoder The following commands are used to control the speed and stop bits of the RS-485 bus.
- Page 8 7E 00 11 90 00 13 A2 00 41 8C 58 B6 FF FE C2 7D 01 00 00 00 A2 Emulator Version Communications Protocol The Emulator Version of the RS485 modem is ideal for customers who are already using NCD wireless sensors and wish to adapt existing RS485 messages to follow NCD standards for device communications. The Emulator version essentially takes incoming RS-485 data and attaches additional information to make existing equipment act like a modern NCD IoT sensor.
- Page 9 This RS485 Sensor converter works in a different way. In order to send data to it user will need to include the payload header, node id and sensor type. For example the entire payload was 7F 00 FF FF 85 85 85. Packet Structure: 7F - Payload header 00 - Node ID...
- Page 10 7E 00 13 10 00 00 00 00 00 00 00 FF FF FF FE 00 00 F2 02 00 00 00 00 Set Encryption Key: Note this command sets the device to the default NCD wireless encryption key: 55 AA 55 AA 55 AA 55 AA 55 AA 55 AA 55 AA 55...
- Page 11 AA 55 AA 55 FF B1 RS-485 Serial Settings – Emulator The following commands are used to control the speed and stop bits of the RS-485 bus. Get Stop Bits: 7E 00 10 10 00 00 00 00 00 00 00 FF FF FF FE 00 00 F7 0D F0...