devLib2  2.7
devLib2 MMIO Bus Access Library

What is it?

devLib2 is an extension to the EPICS OS independent VME bus access library (devLib v1) found in the 3.14.x series. The v2 library is an overlay and extension to the v1 library and not a replacement. It is planned that the v2 library will be merged with the v1 library for the 3.16.x series. After that point devlib2 will continue to exist as a location for backports and bug fixes for the 3.14.x and 3.15.x series.


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devLib2 adds features in several areas: PCI bus access, VME64x CSR/CSR, and memory mapped I/O (MMIO) operations.


The PCI bus access interface is entirely new. It is currently implemented for RTEMS and vxWorks. An implementation for userspace Linux is also under development. The PCI interface provides functions for: searching the bus, mapping devices into process memory, and (dis)connecting interrupts.

Runtime selection of implementations is also supported. This allows code using this interface to compile and link for all target, even those which lack an implementation.


The VME64x library provides several functions for accessing the CSR/CR address space defined by VME64 and extended by VME64x. This includes: probing by slot number and matching by identifier registers, definitions of standard registers, and functions to access them.


The MMIO library provides an OS and CPU architecture independent way to safely access memory mapped I/O devices. Makes guarantees of the width and order of accesses.


2.7 (Jan. 2016)

2.6 (May 2015)

Work by Andrew Johnson

Work by Till Straumann

Work by Dirk Zimoch

Work by Michael Davidsaver

2.5 (May 2014)

2.4 (Oct. 2012)

2.3 (Apr. 2012)

2.2 (Sept. 2011)

2.1 (Jan. 2011)

2.0 (Sept. 2010)

Michael Davidsaver
Till Straumann
Dirk Zimoch