Its pretty easy to write your own code to do this. The 8052-basic goes into what might be called a standalone mode when EPROM programming is going on- it stops treating the external ROM as memory and as a device with three ports (High/low address and data). The address is set AND HELD, the DATA is SET AND HELD for the programming time (when PROG is active and Vpp is driven up)then DATA is READ. The programming time is "soft" in that it isn't part of the memory fetch execute cycle. You can get the BASIC-52 source and find out how to hack it.