[Info-vax] Changed Boot behavior on XP1000 since 2013

[MichaelM]

Now we are able to read the hwc on XP1000; :

>>> e -b toy:0 -> secs
       e -b toy:2 -> mins
       e -b toy:4 -> hrs
       e -b toy:7 -> date
       e -b toy:8 -> month
       e -b toy:9 -> year offset
or together without secs
       e toy:2 -w -n 3
shows 4 (-n 3) halfwords (-w) beginning with address 2 (toy:2).

So we have made some tests on our XP1000 and have noticed:

>>> e toy:2 -w -n 3 shows the hwc time correct beginning with minutes and using year 2000 as base time (tested for years 2012 and 2013).
After an >>> INIT on the boot prompt or after a power off (poweroff
results in an INIT), the firmware changes the year byte if the byte is
greater than 0C (0C -> 0C, 0D -> 5D, 10 -> 60).

The hwc shows this behavior:

VMS time 31.12.2012 23:45   2  772E       2E = 46 minute
                                            4  BB17      17 = 23 hour
                                            6  1F02       1F = 31 Day
                                            8  0C0C       0C = 12
Month
                                                               0C = 12
Year + 2000 = 2012

after Poweroff                         2  7732        32 = 50
                                             4  BB17
                                             6  1F02
                                             8  0C0C

after Poweroff for ~ 25 min       2  7712        12 = 18 minute
                                             4  BB00       00 = 00
hour
                                             6  0103        01 = 01
Day
                                             8  5D01        01 = 01
Month
                                                                5D =
93 Year + 2000 = 2093 ?

boot with                                2  770A        0A = 10
25-jan-2013 14:05                   4  BB0E        0E = 14
after shutdown                        6  1903         19 = 25
                                             8  0D01         01 = 01
                                                                 0D =
13 Year + 2000 = 2013

>>>INIT                                  2  770D        0D = 13
                                              4  BB0E       0E = 14
                                              6  1903        19 = 25
                                              8  5D01        01 = 01
                                                                 5D =
93

boot with 31.12.2012 23:50       2  7737        37 = 55
                                              4  BB17       17 = 23
                                              6  1F03        1F = 31
                                              8  0C0C        0C = 12
                                                                  0C =
12

 after 10 minutes                      2  7700         00 = 00
                                              4  BB00        00 = 00
                                              6  0104         01 = 01
                                              8  0D01         01 = 01
                                                                  0D =
13    ,  after >>>INIT  0D -> 5D.

We have noticed too, that after year 2041 the time stays correct after
an INIT, so only years between 2013 and 2040 (28 years) seem to be
affected.
My old Alphastation 200 4/233 is not affected and boots fine with VMS
V8.4.