hull@hao.ucar.edu (Howard Hull) (01/28/89)
I have the following (via USnail) from Jack Aker, who does not have Usenet
posting access. I haven't had a chance yet to check it against my Insider
RTClock modules, since I am doing this on my A2000 at work, and the Insiders
are installed in my A1000s at home.
-soh-
January 20, 1989
The RTClock program provided with the Insider memory board from
Michigan Software has a "year after leap year" bug. The program
reads and displays the correct date, but the DOS value set is one
day earlier than the displayed date.
The two code segments below show the bug and the correction for
it.
?U DoIO+8b0
00c7eb28: 202e ffe4 move.l -1c(a6),d0
00c7eb2c: 7204 moveq #4,d1
00c7eb2e: 4eb9 00c7 f458 jsr c7f458
00c7eb34: 5581 subq.l #2,d1
00c7eb36: 6612 bne.s *+12 ;c7eb4a ;wrong place
00c7eb38: 0cae 0000 0002 ffe8 cmpi.l #2,-18(a6)
00c7eb40: 6f08 ble.s *+8 ;c7eb4a
00c7eb42: 06ae 0001 5180 fffc addi.l #15180,-4(a6)
00c7eb4a: 206e 0008 movea.l 8(a6),a0
00c7eb4e: 20ae fffc move.l -4(a6),(a0)
This is what the above code segment should be:
?U DoIO+8b0
00c7eb28: 202e ffe4 move.l -1c(a6),d0
00c7eb2c: 7204 move.q #4,d1
00c7eb2e: 4eb9 00c7 f458 jsr c7f458
00c7eb34: 5581 subq.l #2,d1
00c7eb36: 6608 bne.s *+8 ;c7eb40 ;correct
00c7eb38: 0cae 0000 0002 ffe8 cmpi.l #2,-18(a6)
00c7eb40: 6f08 ble.s *+8 ;c7eb4a
00c7eb42: 06ae 0001 5180 fffc addi.l #15180,-4(a6)
00c7eb4a: 206e 0008 movea.l 8(a6),a0
00c7eb4e: 20ae fffc move.l -4(a6),(a0)
Use a binary file zap tool to change the '6612' to '6608', which
will correct the wrong branch destination.
The byte to change from 12 hex to 08 hex is at the following
places in the different versions as shown:
RTClock size date offset in file
V ?? 8864 12-Feb-87 90F
V2.0 8904 16-Sep-87 9CB
There may be other versions of RTClock. If your copy doesn't
match either of the versions above. Search for the hex string:
5581 6612 0cae 0000 0002 ffe8 6f08 06ae 0001 5180
||
08 goes here
There should be only one place in the file with this string.
Jack Aker
6944 Burnside Dr.
San Jose CA 96120
-eom-
Posted by Howard Hull
hull@hao.ucar.edu451061%UOTTAWA.BITNET@CORNELLC.CIT.CORNELL.EDU (Valentin Pepelea) (01/29/89)
In Message-ID: <1334@ncar.ucar.edu> Howard Hull <hull@hao.ucar.edu> writes: > I have the following (via USnail) from Jack Aker, who does not have Usenet >posting access. I haven't had a chance yet to check it against my Insider >RTClock modules, since I am doing this on my A2000 at work, and the Insiders >are installed in my A1000s at home. >-soh- > > (rtClock patch followed) That was real nice of you. Now could you please ask Jack Aker to make rtClock work with my 68020/68881 board. It is a Lucas board to be exact. When executed, rtClock starts printing garbage in my window until eventually the Guru starts meditating. Perhaps it would be nice to post a new version of rtClock in uuEncoded form. After all, it will be of use to only those who already have an Insider board. Patches are so difficult and unpleasant to install. _________________________________________________________________________ "An operating system without Name: Valentin Pepelea virtual memory is an operating Phone: (613) 233-1821 system without virtue." Bitnet: 451061@uottawa Usenet: Look at the header - Ancient Inca Proverb Planet: Earth