Thankyou everyone for your input.
I figured it out early this morning. It was the crystal I was using, it did not work with the SCK frequency.

One thing that I have had difficulty with is reading the signature bytes. Here is the only reference in the datasheet as to where the signature bytes are located.

(000H) = 1EH indicates manufactured by Atmel
(100H) = 52H indicates AT89S52
(200H) = 06H

Forgive my ignorance, but I have NO IDEA what these addresses mean? I learned by trial and error on what address to read the signature bytes from.
ADDR Byte
20h = 1EH
21H = 52H
22H = 06H

Now it reads perfect every time.

Another problem (maybe the datasheet is wrong) is in the erase command. According to the datasheet, the 89S52 requires a 500mS
delay after the command is sent. This seems quite long. Could this be a mistake?

at any rate its working perfectly. Some of the ATMEL datasheets are very detailed (i.e. AVR) while others are not.

Thanks again
CT