How can i download pgm in to 89s51 using USB cable. Because I am using Laptop
Woops sorry, brain is still waking up. So addendum it does require that the ISP be already programed into the device so if you want to use a laptop, with usb interface to program it, and you do not have a device programmer borrow someones prior and put the uart ISP into it. (they have this note too www.atmel.com/.../doc4218.pdf)
The other option is to use an FTDI device that supports SPI (see the data sheet www.atmel.com/.../doc2487.pdf). You will have to either 'do it yourself' for the programming or find someone who has already written the software to program it this way.
However this thread http://www.keil.com/forum/docs/thread6177.asp
and this company might be a start as well http://www.xeltek.com Search for your device www.xeltek.com/.../page2.php*&prog_type=1000&manufacturer=ATMEL&company=0
have fun
Stephen
Could I make any conversion USB to serial in software Other then Hardware . Is there any Idea ..