Hello, Please refer to Lash Magic User Manual page 41 and the following lines.
"The following simplified circuit diagram for an 89C51RD2 is one possible way of connecting the DTR and RTS signals to RST and /PSEN of the device. Note that minor changes would have to be made to use this circuit with the XA devices."
It says minor changes are required for XA devices. I would like to know what are they. Thanks. Nitin