You're right Andy, I'm just starting with the Keil tool. But as it's for own applications I couldn't afford to buy the uVision 2.
I've bought the uVision 1 from a compagny which wasn't using it anymore. So they've sold it to me for a low price. There was only the software and no documentation. I suppose that it was going to the trash. That's why I'm working with the uVision 2 PDF files.

Concerning my question, I've found one of the problems !
The two variables were declared as 'xdata' .... Sorry !

But now, when building, and error message (#249) from the compiler tells me that the DATA segment is too large. This seems as if the whole RAM was not declared, and this is the case.

In the linker's option dialog box, the acceptable maximum value for RAMSIZE is 256 bytes. How could I specify that the RAM size is 1Kbyte ?
I was thinking that these 256 bytes were IDATA, and the 768 following bytes (ERAM) should be PDATA. However, there is not option for the compiler concerning memory segments declaration. This is only available on the linker, but the error message is on the compiler output.
I'm using the small memory model.

What does it mean ?
Should I declare the segments in the code ?

I hope not bother you with these basic questions but I'm not familar with chaintool settings. For my job, I'm used to work with chaintools correctly initialized.

Thanks
Stephane