baud

Elixir Serial Port with Modbus RTU.

Installation and Usage

Add baud to your list of dependencies in mix.exs:

def deps do
  [{:baud, "~> MAJOR.MINOR"}]
end

Enumerate your serial ports.

["COM1", "/dev/ttyUSB0", "/dev/tty.usbserial-FTVFV143"] = Baud.Enum.list()

Interact with your serial port.

# this echo sample requires a loopback plug
tty =
  case :os.type() do
    {:unix, :darwin} -> "/dev/tty.usbserial-FTYHQD9MA"
    {:unix, :linux} -> "/dev/ttyUSB0"
    {:win32, :nt} -> "COM5"
  end

{:ok, pid} = Baud.start_link(device: tty)

Baud.write(pid, "01234\n56789\n98765\n43210")
{:ok, "01234\n"} = Baud.readln(pid)
{:ok, "56789\n"} = Baud.readln(pid)
{:ok, "98765\n"} = Baud.readln(pid)
{:to, "43210"} = Baud.readln(pid)

Baud.write(pid, "01234\r56789\r98765\r43210")
{:ok, "01234\r"} = Baud.readcr(pid)
{:ok, "56789\r"} = Baud.readcr(pid)
{:ok, "98765\r"} = Baud.readcr(pid)
{:to, "43210"} = Baud.readcr(pid)

Baud.write(pid, "01234\n56789\n98765\n43210")
{:ok, "01234\n"} = Baud.readn(pid, 6)
{:ok, "56789\n"} = Baud.readn(pid, 6)
{:ok, "98765\n"} = Baud.readn(pid, 6)
{:to, "43210"} = Baud.readn(pid, 6)
{:ok, ""} = Baud.readn(pid, 0)

Baud.write(pid, "01234\n")
Baud.write(pid, "56789\n")
Baud.write(pid, "98765\n")
Baud.write(pid, "43210")
:timer.sleep(100)
{:ok, "01234\n56789\n98765\n43210"} = Baud.readall(pid)

Baud.stop(pid)

Connect the RTU master to the testing RTU slave:

# run with: mix slave
alias Baud.Slave
alias Baud.Master

tty0 =
  case :os.type() do
    {:unix, :darwin} -> "/dev/tty.usbserial-FTYHQD9MA"
    {:unix, :linux} -> "/dev/ttyUSB0"
    {:win32, :nt} -> "COM5"
  end

tty1 =
  case :os.type() do
    {:unix, :darwin} -> "/dev/tty.usbserial-FTYHQD9MB"
    {:unix, :linux} -> "/dev/ttyUSB1"
    {:win32, :nt} -> "COM6"
  end

# start your slave with a shared model
model = %{
  0x50 => %{
    {:c, 0x5152} => 0,
    {:i, 0x5354} => 0,
    {:i, 0x5355} => 1,
    {:hr, 0x5657} => 0x6162,
    {:ir, 0x5859} => 0x6364,
    {:ir, 0x585A} => 0x6566
  }
}

{:ok, slave} = Slave.start_link(model: model, device: tty0, speed: 115_200)
{:ok, master} = Master.start_link(device: tty1, speed: 115_200)

# read input
{:ok, [0, 1]} = Master.exec(master, {:ri, 0x50, 0x5354, 2})
# read input registers
{:ok, [0x6364, 0x6566]} = Master.exec(master, {:rir, 0x50, 0x5859, 2})

# toggle coil and read it back
:ok = Master.exec(master, {:fc, 0x50, 0x5152, 0})
{:ok, [0]} = Master.exec(master, {:rc, 0x50, 0x5152, 1})
:ok = Master.exec(master, {:fc, 0x50, 0x5152, 1})
{:ok, [1]} = Master.exec(master, {:rc, 0x50, 0x5152, 1})

# increment holding register and read it back
{:ok, [0x6162]} = Master.exec(master, {:rhr, 0x50, 0x5657, 1})
:ok = Master.exec(master, {:phr, 0x50, 0x5657, 0x6163})
{:ok, [0x6163]} = Master.exec(master, {:rhr, 0x50, 0x5657, 1})

:ok = Master.stop(master)
:ok = Slave.stop(slave)

Testing

# test with socat ttys
./test.sh
# test with custom ttys (null modem)
export TTY0="/dev/ttyUSB0"
export TTY1="/dev/ttyUSB1"
mix test
#in Windows
#requires COM98/COM99 com0com ports
test.bat

Development

Windows

Install Visual C++ 2015 Build Tools by one of the following methods:

Download and install visualcppbuildtools_full.exe
Thru Chocolatey choco install VisualCppBuildTools.

From the Windows run command launch cmd /K c:\Users\samuel\Desktop\baud\setenv.bat adjusting your code location accordingly.

Ubuntu

Give yourself access to serial ports with sudo gpasswd -s samuel dialout. Follow the official Elixir installation instructions and install build-essential erlang-dev as well.

MacOS

Give yourself access to serial ports with sudo dseditgroup -o edit -a samuel -t user wheel.

Roadmap

Future

Remote compile mix task to Linux & Windows

0.6.1

Added test.bat for Windows com0com ports

0.6.0

Using now the transport and protocol behaviors defined in modbus package

0.5.7

Updated to sniff 0.1.7
Updated to modbus 0.3.9
Added RTU slave for testability
Master module rewrite for readability
Baud module rewrite for readability

0.5.6

Updated to sniff 0.1.6 (bug fix)
Test with fake socat ttys
Full posix tty paths required
Pass test serial port thru environment variables

0.5.4

Updated to sniff 0.1.4

0.5.3

Updated to sniff 0.1.3
Document Windows/Ubuntu dependencies

0.5.2

Updated to sniff 0.1.2 need for ´iex -S mix´ to find native library in Elixir 1.5.1
Updated to modbus 0.3.7

0.5.1

Updated to sniff 0.1.1
Extract NIF to its own repo (sniff)

0.5.0

Posix NIF implementation
Win32 NIF implementation
Baud api simplification
Refactored to NIF for improved speed and test isolation
Removed sock/loop (will be implemented as part of forward)

0.4.3

Add wait4ch to handle non standard line/packet terminators

0.4.2

Port proxy added to ensure proper closing on exit status msg
Kill tests added for both baud and sock
Refactored from genserver to actor

0.4.1

Updated Makefile for Windows 10

0.4.0

Added sample script (1 y 2)
Improved documentation
Update to modbus 0.2.0 (refactoring required)

0.3.0

Integration test script for modport
Added test.sh to isolate tests run
RTU master, slave, and tcpgw loop modes
Serial port export to socket in raw, text, and modbus mode
RTU API matched to modbus package (1,2,3,4,5,6,15,16)
Improved timeout handling for shorter test times

0.2.0

Interactive RTU: read/write up to 8 coils at once

0.1.0

Cross platform native serial port (mac, win, linux)
Modbus (tcu-rtu), raw and text loop mode

samuelventura/baud