For programming the AT89C51 series of ATMEL, you need :

- working serial interface TTL level.
- PSEN set low during reset
- AE tide high by pull-up.
- XTL compatble to your baudrate.
- VCC on all pins
- GND on all pins.

Startup FLIP software.
Select device
Select communication port
reset hardware WITH PSEN low.
Use connect button
select the actions (erase, programm ,...)
push START button
and wait.

disconnect
PSEN release from GND and reset again to startup your code.

Maybe you must program the SFR bits also.

BLJB bit set to false to start your firmware application.


Best Regards.