It does, since it provides clarity on how Intel originally intended the 8051 to function. Whether all derivatives adhere to it is another matter entirely. (I didn't go to the trouble, so nice find, btw :-))

There is also the problem of Atmel's interpretation of 'the bible', apparently lacking in some detail (like the above) and including mention of their x2 clock speedup feature (among other possible inconsistencies) that are not included in the original Intel document. Reason I linked to it instead of Intel's original was it appeared to be more relevant to Robin's processor variant of choice (the AT89S52).


Regards Valentin
PS: I've always had a fascination with electronic music instruments, and would be very interested to hear more about your project..