obj files compatibility

.obj files are used by the linker and thus has nothing to do with any assembler.

E$rik

"I'm beginner in 8051 programming."

If you're just starting out, why not start with a clean tool set?
Why confuse the issue with a Keil compiler, Brand-X assembler, Brand-Y Linker, etc??

All of the Keil toolsets that include the compiler also have the assembler - so, if you have the Keil compiler, you must also have the corresponding Keil assembler!

"I'm beginner in 8051 programming."

Standard advice:

First, you need to read the uVision Getting Started guide, and work through the example projects in it.

You need to read the following documents - commonly referred to as "the bible" for the 8051:

http://www.semiconductors.philips.com/acrobat/various/80C51_FAM_ARCH_1.pdf
http://www.semiconductors.philips.com/acrobat/various/80C51_FAM_PROG_GUIDE_1.pdf
http://www.semiconductors.philips.com/acrobat/various/80C51_FAM_HARDWARE_1.pdf

Are you also a newbie to 'C' programming in general?
If so, you'll also need a good 'C' textbook.

Here are some other introductory & reference materials:
http://www.keil.com/books/8051books.asp
http://www.8052.com/books.phtml
http://www.8052.com/tutorial.phtml

Thank for having rely so quickly ;-)

But... in my office, we have another assembler (intel), and for an application we must use float and trigonometric functions also with Keil C compiler I want doing a obj file with the compute functions for linking them with the other assembler (because this application was already developp with this).

Now I hope you understand my problem.

Keil A51 is compatible with Intel ASM-51. You should be able to assemble intel ASM-51 files with Keil A51.

If not, you can still link the obj file created by ASM-51. Just add it into the project like you would for any other obj file. In uVision2, when Adding filesto a group, just select the obj file.

Jon