Linux Simple I/O Library

libsimpleio is an attempt to encapsulate (as much as possible) the ugliness of Linux I/O device access. It provides services for the following types of I/O devices:

• Industrial I/O Subsystem A/D (Analog to Digital) Converter Devices
• Industrial I/O Subsystem D/A (Digital to Analog) Converter Devices
• GPIO (General Purpose Input/Output) Pins
• Raw HID (Human Interface Device) Devices
• I²C (Inter-Integrated Circuit) Bus Devices
• Labview LINX Remote I/O Devices
• PWM (Pulse Width Modulated) Output Devices
• Serial Ports
• SPI (Serial Peripheral Interface) Bus Devices
• Stream Framing Protocol Devices
• TCP and UDP over IPv4 Network Devices
• Watchdog Timer Devices

Although libsimpleio was originally intended for Linux microcomputers such as the Raspberry Pi, it can also be useful on larger desktop Linux systems.

The C wrapper functions exported by libsimpleio all follow the same uniform pattern:

• All C wrapper functions are proper procedures (void f() in C).
• All input arguments of primitive types (int, float, etc.) are passed by value.
• All output arguments of primitive types are passed by reference (int *, float *, etc.).
• All composite types are passed by reference.
• int32_t is used wherever possible for int and bool arguments.

All of the C wrapper functions are declared between _BEGIN_STD_C and _END_STD_C for C++. Binding modules are provided for Ada, C#, Java, and Free Pascal. Additional source code libraries are provided for Ada, C++, C#, Java, and Free Pascal that define OOP (Object Oriented Programming) classes for libsimpleio.

News

• 9 January 2019 -- Continued working on the Ada Remote I/O code. Continued working on the Pascal Remote I/O code. Compiling Pascal Remote I/O client programs on Windows is now supported.
• 16 January 2019 -- The C wrapper function source files have been moved to the c/ subdirectory. The source code is now published on GitHub at https://github.com/pmunts/libsimpleio. The old repository at http://git.munts.com (which actually just mirrors a private Subversion repository and then pushed to GitHub) will be maintained, but you should clone from GitHub, which will be much faster.
• 8 February 2019 -- Reworked PWM device handling for the Linux 4.19 kernel. Cleaned up some stale links and commands in the user manual. Cleaned up some loose ends in the MY-BASIC bindings and example programs.
• 12 March 2019 -- The Debian native packages now depend on libhidapi-dev, for Remote I/O over USB raw HID.
• 10 June 2019 -- Material from the Controlling I/O Devices with Ada using the Remote I/O Protocol educational tutorial at the Ada-Europe 2019 conference is available at http://git.munts.com/ada-remoteio-tutorial.
• 18 July 2019 -- Packages for Debian 10 (Buster) are now available at http://repo.munts.com/debian10.
• 5 August 2019 -- Started adding .Net Core example programs using RemObjects Elements.
• 8 January 2020 -- Added LINUX_errno(). Added libmodbus bindings and objects for Ada.

Documentation

The user manual for libsimpleio is available at http://git.munts.com/libsimpleio/doc/UserManual.pdf

The man pages specifying the libsimpleio API are available at libsimpleio.html

Git Repository

The source code is available at:

https://github.com/pmunts/libsimpleio

Use the following command to clone it:

git clone https://github.com/pmunts/libsimpleio.git

Package Repository

Prebuilt packages for Debian Linux are available at:

I am available for custom system development (hardware and software) of products using ARM Linux or other microcomputers.