The PG302 with no adapters lets you program the following microcontrollers:
Add the ADT87 Adapter :
AMD: 87C51, 87C52, 87C521, 87C541
Atmel: 89C51, 89C52, 89C55, 87F51, 87F52
Intel: 8751BH, 8752BH, 87C51, 87C51FA, 87C51FB, 87C52, 87C54
Phillips: 87C51, 87C51FA, 87C51FB, 87C52, 87C504, 87C524, 87C528, 87C550, 87C575, 87C576, 87C652, 87C654
Add the ADT90 Adapter to program the following microcontrollers:
Atmel: 90S4414, 90S8515, 89S53, 89S8252
Add the PLCC Adapter in combination with above adapters to program any of the PLCC versions of those chips.
Many AVR chips (2313, 2323, 2333, 2343, 4433, 4434, 8515, 8535, MEGA161, MEGA163) can be programmed indirectly.
The PG302 also supports in circuit programming with the ISP302.