On 2014-07-10 17:38, George Kozakos wrote: >> ... showing mostly that STCKCONV (as of z/OS 1.13) has not yet >> implemented the (proposed) use of the high byte of STCKE when >> the ETOD clock wraps. > > Support for the 2nd epoch was added in z/OS 2.1 > Yup. I tried it on a 2.1 system, and it seems good until about 2185. I don't know why they didn't go for still more bits -- it's simplest not to mask off any. But:
o It hardly matters. o In the future, (some of) those additional 7 bits may be used for purposes other than extending the range of the ETOD clock. But I believe someone has pointed me to a publication saying that the entire high byte of ETOD is already committed for that extended (unsigned) range. Long ago, I wondered why ETOD couldn't still be defined as signed; it seems to me that CE 1899 might be more useful than CE 38434 (or so). At that time, I was told that there already existed a firm specification that ETOD was a 128-bit (minus programmable area) unsigned item. I suppose programmers might already be loading its comparator with 16X'FF' to defer an interrupt ridiculously far. (Is there an ETOD comparator register?) Thanks, gil
