s51dude is an In-System programming tool specifically designed to
be used with the usbtinyisp board and the Atmel's 8051 family of
micrcontrollers.

This program is intended to cover the need of the 8051 developer who
wants to program the devices with computers without parallel or serial
port. The only alternative left is to use the USB port.  That is when
you will need s51dude.

It's written in C.
