Introduction

raw-device is base module to remotely control devices using LAN/TCP or RS-232/serial connections. The device control protocal must be based on sending and receiving sequence of bytes/ASCII characters in request-response schema which is a common for communication protocols.
A base object RAW is thought to be a prototype for other, more specific communication objects, but can be also used as stand-alone, full-functional object for simple scenarios.

Main features

• different modes of connect-disconnect cycle
• requests queuing and timing management
• events driven
• easy extensible
• response data auto management

Usage

const RAW = require('raw-device');

//send-receive data for TCP socket device
const dev1 = new RAW({host: '192.168.4.31', port: 9761});
dev1.emitter.on('device_data', data => console.log(data));
dev1.process('fa 01 00 ff\n');

//send data for Serial device
const dev2 = new RAW({path: 'com2'});
dev2.process('00x00x00x00x14x60', '3Bx78x5D');

RAW Object

The primary exported object is RAW, which you'll use directly to communicate with serial or tcp devices or use as prototype for you own objects. This section covers direct use.

Constructor new RAW(AddressObject, OptionsObject)

• AddressObject <Object>

  • name <string> default: 'RAWdevice'
    //for serial
  • path <string> Use valid serial path available in system. In Windows it is com1, com2 etc. In Linux it is /dev/ttyS0, /dev/ttyS1 and so on. It is required and has no default value.
  • baudRate <number> default 9600
  • dataBits <number> default 8
  • parity <string> default 'none'
  • stopBits <number> default 1
    //for tcp
  • host <string> Use valid IP address. No default value, it is required
  • port <number> default 23

• OptionsObject <Object>

  • encoding <string> - default 'ASCII'
  • duration <number> default 1500 ms. Inter-command period [ms]. A time for device to process command and to prepare and send a response.
  • disconnect <boolean|number> default true. Connecion cycle scheme. Use true, false or timeout[ms]. True means close connection when command queue is empty, false means do not close connection, number means close connection after time of connection inactivity.
  • splitter <Stream> transform stream to merge incoming data chunks and split data into valid responses. Only single property among delimiter, regex, timeout can be used
    • delimiter <string> default '\r\n' Split incoming data into valid responses using string delimiter
    • regex <Regex> efault /[\r\n]+/. Split incoming data using regular expression
    • timeout <number> default 1100 ms. Timer based splitting. Response is completed if inter-byte time is longer then timeout. Please consider that timeout must be shorter than duration (inter-command period) and disconnect time (if disconnect use timeout scheme)

Method process(...commands)

Commands can be regular strings or hexadecimal encoded strings. Hexadecimal strings can use x, :(colon) or -(minus) as separator.

Internal commands

There are some internal commands which starts with #. They are not sent to device, but are processed by RAW itself.

• #pause number - Append additional pause between neighboring commands as number of miliseconds.

Event: responseFromDevice

Emited when device response is properly decoded.

• response <Object>
  • dev <string> - device name
  • raw <Buffer> - not decoded raw response
  • value <string> - response decoded to string value

Event: commandForDevice

Emited when command is properly encoded and sent to device. Of course only encoded property is sent to device itself.

• command <Object>
  • name <string> - device name
  • command <string> - a command itself, not parsed or encoded
  • encodedstr <string> - command encoded as string
  • encoded <Buffer> - command encoded as Buffer
  • duration <number> - time [ms] for device to process the command (and generate a possible response).

Event: 'connectionData'

A data which comes directly from device port "as is". Not decoded, merged or chopped by splitter.

• data <Buffer>

Event: 'connectionStatus'

Emited when device connection status changes.

• statusObj <Object>
  • dev <string> - device name
  • address <string> - device address as string
  • status <string> - connection status
  • more <string|Object> - additional status information