# baud
Elixir Serial Port with Modbus RTU.
## Installation and Usage
1. Add `baud` to your list of dependencies in `mix.exs`:
```elixir
def deps do
[{:baud, "~> 0.5.1"}]
end
```
2. Enumerate your serial ports.
```elixir
["COM1", "ttyUSB0", "cu.usbserial-FTVFV143"] = Baud.Enum.list()
```
3. Interact with your serial port.
```elixir
tty = case :os.type() do
{:unix, :darwin} -> "cu.usbserial-FTYHQD9MA"
{:unix, :linux} -> "ttyUSB0"
{:win32, :nt} -> "COM12"
end
#Try this with a loopback
{: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.readch pid, 0x0d
{:ok, "56789\r"} = Baud.readch pid, 0x0d
{:ok, "98765\r"} = Baud.readch pid, 0x0d
{:to, "43210"} = Baud.readch pid, 0x0d
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
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
```
4. Interact with your **RTU** devices.
```elixir
alias Modbus.Rtu.Master
tty = case :os.type() do
{:unix, :darwin} -> "cu.usbserial-FTVFV143"
{:unix, :linux} -> "ttyUSB0"
{:win32, :nt} -> "COM10"
end
#rs485 usb adapter to modport
{:ok, pid} = Master.start_link([device: tty, speed: 57600])
#force 0 to coil at slave 1 address 3000
:ok = Master.exec pid, {:fc, 1, 3000, 0}
#read 0 from coil at slave 1 address 3000
{:ok, [0]} = Master.exec pid, {:rc, 1, 3000, 1}
#force 10 to coils at slave 1 address 3000 to 3001
:ok = Master.exec pid, {:fc, 1, 3000, [1, 0]}
#read 10 from coils at slave 1 address 3000 to 3001
{:ok, [1, 0]} = Master.exec pid, {:rc, 1, 3000, 2}
#preset 55AA to holding register at slave 1 address 3300
:ok = Master.exec pid, {:phr, 1, 3300, 0x55AA}
#read 55AA from holding register at slave 1 address 3300 to 3301
{:ok, [0x55AA]} = Master.exec pid, {:rhr, 1, 3300, 1}
```
## Roadmap
0.5.2
- [ ] Remote compile mix task to Linux & Windows
- [ ] Document deploy dependencies
0.5.1
- [x] Updated to sniff 0.1.1
- [x] Extract NIF to its own repo (sniff)
0.5.0
- [x] Posix NIF implementation
- [x] Win32 NIF implementation
- [x] Baud api simplification
- [x] Refactored to NIF for improved speed and test isolation
- [x] Removed sock/loop (will be implemented as part of forward)
0.4.3
- [x] Add wait4ch to handle non standard line/packet terminators
0.4.2
- [x] Port proxy added to ensure proper closing on exit status msg
- [x] Kill tests added for both baud and sock
- [x] Refactored from genserver to actor
0.4.1
- [x] Updated Makefile for Windows 10
0.4.0
- [x] Added sample script (1 y 2)
- [x] Improved documentation
- [x] Update to modbus 0.2.0 (refactoring required)
0.3.0
- [x] Integration test script for modport
- [x] Added test.sh to isolate tests run
- [x] RTU master, slave, and tcpgw loop modes
- [x] Serial port export to socket in raw, text, and modbus mode
- [x] RTU API matched to `modbus` package (1,2,3,4,5,6,15,16)
- [x] Improved timeout handling for shorter test times
0.2.0
- [x] Interactive RTU: read/write up to 8 coils at once
0.1.0
- [x] Cross platform native serial port (mac, win, linux)
- [x] Modbus (tcu-rtu), raw and text loop mode
## Development
- Use clang-format atom package
## Research
- [ ] Support udoo neo
- [ ] Support beaglebone black
- [ ] Support raspberry pi 3 B
- [ ] Assess rewriting the windows native code using the win32 api
- [ ] Assess rewriting the windows native code using c#/.net
- [ ] Split into a core package and OS dependant packages holding native code
- [ ] loop* tests still show data corruption when run all at once
- [ ] Implement Modbus ASCII support (no available device)
- [ ] Implement DTR/RTS control and CTS/DSR monitoring
- [ ] Implement separate discard for input and output buffers
- [ ] Unit test 8N1 7E1 7O1 and baud rate setup against a confirmed gauge
- [ ] Get port names required for unit testing from environment variables
- [ ] Implement a clean exit to loop mode for a timely port close and to ensure test isolation
- [ ] Improve debugging: stderr messages are interlaced in mix test output
- [ ] Improve debugging: dev/test/prod conditional output
- [ ] Move from polling to overlapped on Windows
- [ ] Research why interchar timeout is applied when reading a single byte even having many already in the input buffer. Happens on MAC.
- [ ] Research how to bypass the 0.1s minimum granularity on posix systems
- [ ] Research higher baud rates support for posix and win32
- [ ] Research Mix unit test isolation (OS resources cleanup)
- [ ] Research printf to embed variable sized arrays as hex strings
