iohw.h - anyone using this?

Marco, iohw.h and its support libraries makes sense because they create a standard interface. The missing part of iohw.h is they are neither a fully developed application interface or a low level interface

Quite a few companies have implemented the named address space parts of 18037 and the direct processor access. The named address and user address parts can accomplish a very portable low level hardware interface. The real role of 18037 is to define the low level interfaces and fixed point math. In hindsight iohw.h was an important stepping stone to understanding what was needed at a low level.

I know some application developers that created higher level application interfaces on this base. (Especially in the cell phone industry)

Regards

-- Walter Banks Byte Craft Limited

Marco wrote:

On the latest draft of the future C standard, found at:

I find no reference to iohw.h. Where is this documented?

ISO/IEC 18037

w,,

here: see section 4 Basic I/O hardware addressing

This is one of those optional add on specs for embedded folks. (Don't expect to see it in Visual C++ anytime soon :) But if most embedded compilers won't provide it then the embedded community won't adopt it and it will rot on the vine. ============================================== " Embedded-C (ISO/IEC TR 18037:2004)

ISO/IEC TR 18037:2004 Extensions to the programming language C to support fixed-point arithmetic, named address spaces and basic I/O hardware addressing. These features are commonly found in embedded processors and are not supported by the standard C language.

Technical Gains Until recently, embedded processors were programmed in assembly language to make use of all the specific performance improving hardware features. By standardizing the C interface it is possible to program embedded processors with their ever increasing complex functionality using a high level language, thereby increasing portability and stability of the programs.

Previous Revisions/Versions Embedded C is largely based on DSP-C, an industry standard defined by ACE and Philips. "

Thanks. I eventually found n1169.pdf, which seems to be a later version (2006). It's on:

I tracked it using ISO/IEC TR 18037:2004 from sc22 (or wg14?) above.