Mahmood, this post was not addressed to you. If you bought the atmel's ISP programmer (ISP cable) containing the 74HC244 instead of 74VHC244, then there's no room for criticism, of course. Nevertheless, the original schematic, which is from september 2001 shows the 74VHC244:

http://www.atmel.com/dyn/resou...p_C_v5.PDF

This post was addressed to people, who refuse to take the 74VHC244, although they are given the original schematic, although they are informed that the 74HCMOS variant will not work and although they finally become the victim of their own faulty design.

The reason for using the 74VHC244 is, that this chip does not contain protection diodes at the inputs (like the 74HC244 does!) to shunt overvoltages to Vcc. The absence of these protection diodes is needed to isolate the Vcc of the to be programmed micro from the line signals of printer port. Why? To allow the micro being powered-up (and powered-down again later) with stable and non-fluctuating ISP bus signals. Especially the reset line must reliably be deactivated during power-up and power-down. Otherwise, the flash code memory is in danger to be corrupted! This Achilles' heel is discussed in tons of application notes from atmel and other manufacturers over and over again. A stable reset during power-up and power-down is urgently demanded for a flash micro! That's the reason, why in the atmel's isp programmer the 74VHC244 must be used, but not the 74HC244! Without the 74VHC244 it's impossible to have the needed control over the ISP bus signals during power-up and power-down!!!

Kai