Erik,
After reading many of your posts, I am beggining to believe that internal watchdogs are a better alternative to the external ones, particulary since we have two sequential writes, rather than just toggling a port pin, but I think there is one point in favour of the external ones, that is external one will try to revive a hung up micro, whereas an internal one will only work after the micro has started working, am I wrong??

"The 1233 is the same w/o the watchdog."
In India the 1233 is much costlier than the the 1232, and 1232 is costiler than the 89C51 microcontroller.

Andy,
Thank you very much for the interest in my post.I think here is nothing wrong with Flash magic, probably my implementation of the hardware interface (I modified it to work with Philips WIN Isp and with your Flash magic)could be the problem, I also tried with your recent revised version with no success, since WIN Isp is working with the same hardware I did not bother to find out the reason. I will try to get the interface circuit(I have now forgotten) and cotact you directly on your email.
Thanks,

John.