RS-232

RS-232 for Linux, FreeBSD and Windows

This is a C++ port of https://gitlab.com/Teuniz/RS-232

Website of the original C library: https://www.teuniz.net/RS-232/

Compiling and Building

Compiling the demos from the example directory can be done as follows:

g++ -I../ DemoRx.cpp ../Rs232.cpp -std=c++11 -Wall -O2 -o test_rx
g++ -I../ DemoTx.cpp ../Rs232.cpp -std=c++11 -Wall -O2 -o test_tx

OR use the provided Makefile by entering make

OR use CMake by entering

cd /path/to/rs232/example
mkdir build
cd build
cmake ..
make

Run the demo by typing:

./test_rx or ./test_tx

To include this library into your project:

1. Put the two files Rs232.h and Rs232.cpp in your project/source-directory.
2. Write #include "Rs232.h" in your source-files that needs access to the library.
3. Add the file Rs232.cpp to your project settings (in order to get it compiled and linked with your program).

A optional standalone documentation can be generated with doxygen by using the Doxyfile in the doc directory.

Usage

You don't need to call rs232::pollComport() when you only want to send characters. Sending and receiving do not influence each other.

The OS (kernel) has an internal buffer of 4096 bytes (for traditional onboard serial ports). USB/Serial-converter drivers use much bigger buffers (multiples of 4096). If this buffer is full and a new character arrives on the serial port, the oldest character in the buffer will be overwritten and thus will be lost.

After a successful call to rs232::openComport(), the OS will start to buffer incoming characters.

Tip: To get access to the serial port on Linux, you need to be a member of the group "dialout".

Note: Traditional (on-board) UART's usually have a speed limit of max. 115200 baud. Special cards and USB to Serial converters can usually be set to higher baudrates.

Attention: When working with virtual connections under Linux by using socat and PTY, the function ioctl in combination wit various arguments (e.g. TIOCMGET) will return with an error (22 invalid argument). Out-commenting #define VIRTUAL_CONNECTION in Rs232.cpp will avoid this issue.

List of Ports

Index	Linux	Windows
0	ttyS0	COM1
1	ttyS1	COM2
2	ttyS2	COM3
3	ttyS3	COM4
4	ttyS4	COM5
5	ttyS5	COM6
6	ttyS6	COM7
7	ttyS7	COM8
8	ttyS8	COM9
9	ttyS9	COM10
10	ttyS10	COM11
11	ttyS11	COM12
12	ttyS12	COM13
13	ttyS13	COM14
14	ttyS14	COM15
15	ttyS15	COM16
16	ttyUSB0	COM17
17	ttyUSB1	COM18
18	ttyUSB2	COM19
19	ttyUSB3	COM20
20	ttyUSB4	COM21
21	ttyUSB5	COM22
22	ttyAMA0	COM23
23	ttyAMA1	COM24
24	ttyACM0	COM25
25	ttyACM1	COM26
26	rfcomm0	COM27
27	rfcomm1	COM28
28	ircomm0	COM29
29	ircomm1	COM30
30	cuau0	COM31
31	cuau1	COM32
32	cuau2	n.a.
33	cuau3	n.a.
34	cuaU0	n.a.
35	cuaU1	n.a.
36	cuaU2	n.a.
37	cuaU3	n.a.

List of Baud Rates

Linux	Windows
50	n.a.
75	n.a.
110	110
134	n.a.
150	n.a.
200	n.a.
300	300
600	600
1200	1200
1800	n.a.
2400	2400
4800	4800
9600	9600
19200	19200
38400	38400
57600	57600
115200	115200
230400	128000
460800	256000
500000	500000
576000	n.a.
921600	921600
1000000	1000000
1152000	n.a.
1500000	1500000
2000000	2000000
2500000	n.a.
3000000	3000000
3500000	n.a.
4000000	n.a.

Available Modes

Field order:

1. [Data-Bits]
2. [Not Set/Even/Odd-Parity]
3. [Stop-Bits]

Available parameters:

Data-Bits	Parity	Stop-Bits
8, 7, 6, 5	N, E, O	1, 2

When in doubt, use default 8N1.