Hello,

I'm trying to upload a .hex file to my AT89S8253, but since it has a lot of differences between the older AT89S8252 i had to use a new software and the solution i found at 8052.com board is VisISP.

I already made the cable using the 74HC126 using the same specifications indicated at http://www.8052.com/visisp52/isp.gif.

But since im not using 8052.com SBC (it's not avaliable on my country and importing would take too long) i need to know the pin setup.

I configured the pin as specified at http://www.8052.com/sbc/schematics/ and i got this

40: VCC (5v)
20: GND

18-19: Crystal (i used 12MHz with 2 33p capacitators)

Is there any other setup i need do arrange?

The software is telling my microcontroller is not connected.

Thanks,