Phillip,

First off, let me say I appreciate your help and patience with an 8051 newbie. :-)

I am using a 89c420 with an 11.0592Mhz crystal. I tried the second program you wrote, and received the same results. Let me go into some more depth with the problem.

When I apply power, both LEDs light up, but one is twice as bright as the other. When I open my communication port with the loader420 program, both LEDs dim to the same brightness. When I invoke the loader (which calls up the DS89C420 LOADER VERSION 1.0 COPYRIGHT (C) 2000 DALLAS SEMICONDUCTOR
>) message, one LED flashes bright then goes off.

Once I program it with any program, one LED lights up completely, and other other one remains off. There is no flashing.

I thought maybe I fried my chip, so as a double checking precaution, I used a second chip with the same results.

Very strange.