i m using old version of BL51, version 4.14. i search for the newer version but couldn't find any. so can i get the link to download BL51(linker/locator),version 5.15 or later
"can i get the link to download BL51(linker/locator),version 5.15 or later"
No, you can't.
The individual tools are not sold separately - only as complete tool-sets.
The available packages are listed here: http://www.keil.com/c51/selector.asp
To contact Keil sales, see http://www.keil.com/company/contact.asp
Note that this forum is not a route to contact either Keil sales ot Keil support: http://www.keil.com/forum/